Maybe that's what you should have done, right there, on the spot, and VERY visibly. I doubt she'd have tried that stunt again. 

I would have civilly told her to get out of my house.  BM knows better than to even come up to our door.  I understand not starting a fight in front of your skid, but have the right to set boundaries in your own home.  Your DH needs to let her know that next time you will file a complaint.

Throw the crazy woman out.  Loudly and let her know if she opens the door and steps in again you will be calling the cops on her for trespassing.  She can stay in the car and you will send the child out.
 

Granted, There's a top level crazy stalker BM in my life, but I wouldn't even let crazy pants come in my front gate the only time she tried that ONCE at drop off years ago.    She never tried that again and pick ups are now elsewhere.

Do not give these women an inch, or she will be rooting around for more than a uniform.

She was worried about waking someone up at 5PM?

I hope your partner really does tell her to not pull that, again.

This is the one and only reason that I am grateful we are long distance. BM will never be in our state. Never at our door. I would probably acted like a crazy person. "Get out NOW. Get out. Get out. Get out!" 

This totally happened to me! Multiple times actually. The first time, I was in the furthest bathroom from the door and my younger skid was on the opposite end of the house. I HAD NO IDEA SHE WAS THERE! I could here my skid talking to someone but maybe she was on the phone?? So when I finally reached the other side of the hosue and I saw BM talking to her, I about screamed and fainted in the same breath. I kept it together though, but my skid was giving me the " do something, make her leave" look.  After she left, my BF got back home with my other skid and I told him about it. He just looked at me and said, "oh i forgot to tell you that she was gonna stop by" UMMMMM Don't you think that would have been information that I NEEDED TO KNOW?!?!?!  I told him to talk to her about just coming in on her own whim but he let it sit and she kept just waltzing in like it was her second home. Finally I had enough. I told him that if he doesn't tell her to AT LEAST knock before coming in, that i was going to be the one to say something. He was like "don't get involved in something that's not going to make a difference. You're just going to make things worse." But he actually did tell her. We still have that boundary problem with her though. But I'm the only one that sees it as an issue.

Our BM stopped in on evening to being the stepbrats browniws "because SM12 doesn't buy enough snacks".  I nearly flipped my lid.  DH said he didn't see a problem with it, because he liked brownies.  He said if she did it again he would allow it.  No made it clear if she did it again he would be tossed out right wing with her and he knew I meant it.   And not that it matters but I used to buy snacks but the hogs would eat them all in one evening.   And leave wrappers everywhere so after several warnings, I stopped.   

I'd like to tell you I'm surprised and shocked but I'm not. I always lock the door when BM does drop offs. Once she tried to open the screen door, I just stared at her in WTF from across the room. 

I'm shocked you were so polite about it, I would have flipped out screaming "WHAT ARE YOU DOING IN MY HOUSE!" Had the phone out dialing 911 and screaming for fear of my life. Let BM have to deal with the cops and claim I was overreacting in my own home to an intruder.

Some people just weren't taught what a boundary and some people were and just don't care.  OP you have a DH problem.  If it was me I would tell him to get of his spineless a** and tell him BM that she is not to just walk into your house anymore and if he doesn't want to do that then you can deal with on your own.  You can send the harpy a letter stating that she is not allowed in your home any longer and if she doesn't respect that then the next time the cops will be called.

She didn't want to wake people up at 5pm????

Yeah, nope.

BM Toxic Troll did that once. When Munchkin SD14 was like 11 or something. We would get a text "on our way for drop off" and DH would THEN unlock the door for Munchkin to saunter in at around 6 am. Toxic Troll worked about 45 mins from our respective lving areas and she would do drop offs tres early. Then DH would do school drop off.

This is when Toxic Troll was actually working for a living.

So, the story goes that she had to park a few cars down, because our driveway was full and a few cars in front of our house and munchkin had to walk to our front door which was unlocked. DH didnt open the unlocked door for kiddo. So Toxic Troll busted into our home yelling at us, calling us names and "eff you guys".Dh got up and told her to get the eff out.

From that day on, she has NEVER been allowed inside our house. Apparently, now that Munchkin is old enough to be alone in the house a few hours, BM thinks it is ok to drop things off and drop by. Munchkin has strict instructions that her mother is never allowed in our home.

In fact, last winter, when she was homeless a few weeks, and we were storing Munchknis things from her apartment, a few garbage bags of things, I told Toxic Troll to place them on the porch. She gave be "the look" and did it, turned around and stalked off. Too bad.

Munchkin isnt dropped off when we arent there, she doesnt have a key.

Look, this is entirely within your pervue to fix. Lock the damned door.  Just telling DH to tell BM to stay out of the house is like pissing into the wind.  If you don't want to a face full of piss, turn around.  Telling the wind to not blow in that direction is ridiculous.

And... why didn't you immediately dial 911 and report a home invasion while physically subduing the perp?

I wouldn't put up with ANYONE coming into my home unannounced unless you live here!  Dear lord. My neighbor and I always knock first, always - and she's welcome at any time.

I would have said, "Excuse me!  What are you doing here? Please leave NOW!"

If BM EVER walked into our house while I was home I would flat out tell her get the f out. Bottom line. 
 

I almost lost it when SD brought our pup outside to her in the driveway when we first got him. (One of the few times she took SD to get her nails done over the past two and half years that SD pays for *insert eye roll*) 

I quickly went out there and was like no he has to go inside. I almost vomited when BM was petting him. Pup was mine, not to be tainted by BMs hands. 
 

SO was like well SD loves pup. Sorry SO, DONT CARE!! Lol. SO knows better now though. 

That is just a big fat NO!! My god I would kill her if BM did that at our home. She did it once very early on in the relationship when I lived in DH's new house at the time, she walked into the kitchen, it's never happened again lets put it that way! And since, we have always lived in joint homes that are both of ours so she wouldnt be that stupid, i know