On this site.  I'll share mine as a DIL, SM SMIL & Biomom.  Basically it is really not about you. It does not mean she likes the ex better than u.  It means that your DH had a life before and  your in laws developed a relationship with the ex.  My own in laws who were lovely people, kept a several photos of my DHs ex on the family wall.  As well as photos of DH & I, our various kids and my family members.  DH divorced under similar circumstances to your DH's--infidelity was involved.  My fil saw me looking at the Ex's photo once and it opened a discussion on their relationship with her--that it was separate from the relationship they had with DH and formed over many years.  He went on to say that EVERY single time the skids came to visit they checked that wall.  He thought it reassured them that they were still very much a part of the family.  I know my in laws lived me through their actions toward me and my children so it wasn't an issue for me.  

As a parent / stepparent I ave formed relationships with partners & spouses that have not endured.  My oldest SS has been married twice and divorced as many times.  Both of his former wives were a part of our family & I became very close with his second wife.  I have pictures of both displayed in my home.  At Thanksgiving my SGD thanked me for keeping them and said it always made her feel welcome and part of our family.

Your in laws may not realize the impact of where this picture is displayed.  You may want to ask your spouse to have a quiet word with his mom about this.  If your relationship is good in other ways I am not sure I'd make this an issue.

At least it will be clear. She may simply keep it since forever and forgot to move away, but the only way to know is to ask. And if she says bs about "she is the mother of my grandkids and she is entitled to have her picture on my table", you may say how you feel and stop seeing them. 

Have you given her a new family photo?

I agree with Crspyew that you may want to ask your spouse to have a quiet word with his mom about.  It would bother me too.

My MIL has family pictures displayed however there are no ex spouses on display, she still has kept those photos in her albums but not on display.

My mother had a framed photo college hung on one of her walls for years that contained a picture of me and my ex together which she totally forgot about, but once I mentioned it to her it was gone. 

I agree especially since it bothers your husband too!!  

As has been said you will get many perspectives on this site and many will tell you it is her house and she can do whatever she likes but she is your husbands mother and he and you should be a priority to her.  Your feelings should be a priority to her.  If your MIL wants to build a bond with you holding onto the past is putting a serious damper on that.  

No reason she can't get a new photo of the kids and it sounds like she has!!

Welcome and good luck to you!!

My MIL just has pictures everywhere and I doubt she thinks one bit about who is in them or who might get offended. If she treats you well otherwise, I'd let it go.  

ETA: Now that I think about it, I don't think she has one single picture of me at all, but she does of BM. But I rarely see her.

I get it. My mom has a digital frame that she had uploaded photos of my XH and I. He was an abusive prick, but convincing my mother of that took time. So, for a long time, in her home, I got to see his face. I understand the pain, resentment, etc.

The question is, is it just a photo, or is it a passive aggressive dig at you and DH? Sometimes a photo is just a photo. It's quite possible that MIL didn't think about it, or she doesn't have a photo of the same size to fit, etc. A chat with MIL and giving her a new photo may fix the problem for your DH and make him comfortable again. 

If the photo is just one more dig at your second family, then your DH still needs to talk to his mother and he needs to start setting up boundaries with his family. If MIL uses that photo as a silent protest against your marriage, then you and DH need to have a conversation about keeping naysayers out of your marriage.

If it's just a photo, I'd let it go. People can display what they want to display, and if after talking to MIL nothing changes, but she treats you all well, I'd just try to put it out of my mind. But if my MIL has shown me disrespect or disrespect for my marriage (which having a photo of an ex on prominent display is debatable about showing disrespect), and the photo is being used as just another dig, I'd start severely limiting my time with my MIL, possibly down to spending no time with her at all. I can deal with people having differing views on photo displays, but I won't tolerate being disrespected and having that disrespect blatantly displayed. It's about intent of the action.

My soon to my MIL has photos of my partner and his ex with their children. And now this past Christmas they've taken more photos, just not with the ex. At this point I don't even care about the photos hanging up on her wall or whatever, but I've deliberately excluded both his kids from any photos I've taken with him. I also don't acknowledge them in any photos he tags me in as well. 

meh I've just learned that people are COMPLETE idiots with zero awareness of what is going on around them. I've dealt with this with FIL and Step MIL....we just stopped going to there house....the photos don't hang on the wall anymore.

The issue for me is not erasing history.......it's the simple fact that divroces are nasty....people act crazy and most times it just ends very badly.....so.....for my DH's dad and step mom to be displaying photos in their home of the EX Wife who tried to (and still does) keep his kids from their son.....totally ruined him financially in the divorce....is nasty to DH and inlaws...who takes  out her divorce issues on the kids.....and gets fall down drunk every day with said kids around......and then drives them around........uhhh yea....to me that is a NO GO and that would make me never enter your home....while that shit was on display.

To this day....4 years post divroce and we even have another child.....DH's mother, father and step mother, my father and my grandparents.....not a single one of those people can move on....they all still live in a life where DH and I are still married to our exes....it makes us sad and angry at the the same time.....and unfortunately.....has tainted the relationships with our family's as we just avoid them....my grandmother just share a facebook memory of my exH and I with our kids....and she captioned it "what  a cute family".

People suck....and DH and I have sworn that we will NEVER do this to our children should they ever get divorced in the future.

My MIL has a very large family photo from when her father was still alive, and it includes BM. It's not in a very visible part of the home, but for holidays, you can clearly see if from the dining room. The thing is, my MIL hates BM with a passion. The woman doesn't curse unless BM's name follows. So, I ultimately don't care about the portrait still being in their home, because in this case, I know this is about MIL's deceased and beloved father, not about BM.  There aren't any other photos of BM anywhere either, whereas there are a bunch of me, DH and my bios along with skids. If the circumstances were different, in which there were more photos around, or MIL still had a relationship with BM, or there were none of me, then yah, it would definitely bother me.

As an aside, when DH and I first moved in together, I worked really hard on creating nice rooms for both SS and SD (who were 7 and 11 at the time). They weren't over the top or anything super fancy, but they were warm, comfortable, and had personal touches. And then BM sent them with a bunch of photos one weekend. Framed. Some with her and each kid. Some of just her. Some with her, DH and the kids during a family vacation. It was over the top. Ultimately, it really bothered me. This wasn't BMs home, and these were not her rooms to decorate or influence. I really didn't want to see her face more than I had to whenever I went to clean. Out of respect for the kids, I asked DH to help them each pick one or two photos. He sent the rest back with the kids. She never sent any more.

Hopefully MIL just does not understand that it is kind of weird to keep that picture up front and center.  Your DH should point the picture out and say something along the lines of..."Hey Ma, you know me and BM divorced years ago and my family is a little different looking now.  (He can say this all like a teasing joke.)  Can I change it out for the other picture of me and the kids and Lettingo?

Ok to those who think that it is ok and have added in their little scenario's about photo albums, or pulling out a stack of photo's that also included BM ......WHAT OP IS DESCRIBING IS NOT THE SAME THING!!!!!!!

Rummaging through an occasional stack of photo's or a photo album that was described as needed to be dusted off is TOTALLY not the same thing as a photo that gets top billing in the family living room, for all to sit and be with every time they visit.  It is wrong and OP has every right to be upset.  

For all making excuses for OP's MIL and all MIL's that display the photo in the living room, keep the pictures in the "guest shared" photo album or pull out stacks of pictures when their new daughter in law is present are not only clueless, they are rude AND insensitive and should be called out on it!!  If by no one else by their son!! 

Keep whatever photos she wants but don't display them in the living room or in guest shared photo albums or pull out stacks of pictures.  OP and all of the "new Daughter in laws are guests in their home and they should worry about making their guests uncomfortable and they should worry more about their own sons and their new daughter in law relationships and let the cheating BM's go!!!  They had their chance to have her as a MIL.... 

And lastly ....... 99.9 % of the MIL are not clueless they know what they are doing.  Anyone should be smart enough to know that of course displaying pictures of another woman, who causes nothing but trouble with their husband would most likely make their son and DIL uncomfortable!!!!!!!!!!  Stop the excuses!!! Someone needs to buy her a clue for Christmas!!!!!!!!!!!!!