Warning, this is a VERY LONG POST about this woman. You are getting all of the details, so that you can really understand what kind of person she is before you give me your opinions and/or advice. I thank you all in advance. This is such a hard thing to deal with, I need outside help. 

Here we go. 

So I am a new stay at home (step) mom to my fiance's 4 year old son. We are all very happy and work through issues pretty well together. I have no kids of my own yet, but hope to have some soon. And I just feel like I was meant to be a mother, so I am loving this mom life. 

But there is one issue we cannot figure out what to do about. And that is the absent bio-mom. She apparently has always been a flake, and lazy and spoiled. Never really took to being a mom in the first place, except when it came to "playing the role" in public. For example, when she does have him, we have sources telling us about how she would snap a few selfies with him, post them on the internet, and then shove an ipad in his face and not want anything else to do with him for the rest of their time together. 

She is 28. She has barely been able to hold a job. And when she doesn't have one, she threatens her parents that they cannot see her son unless they gave her money and paid her bills. They always gave in. She has bounced around from friends houses (who have kicked her out bc she sucks), her parents have kicked her out multiple times, so has her brother. Other than that, she will find an unsuspecting guy and always immediately get them to let her move in. It never lasts more than a few months, bc she sucks. My fiance said she was not working at all, and while he was working 12 hour shifts 6 days a week, would come home to dirty laundry everywhere, piled up dishes, her on the couch watching tv, and her handing him the baby as soon as he gets home bc she's "exhausted". Seriously, this woman is a piece of work. This woman seriously just wants a rich man to take care of her and spoil her and for her to never have to lift a finger a day in her life. And she thinks she deserves it. She acts like she is sixteen years old and not a day older. It is insane. Also, she has an on and off history of pill problems. My fiance had to deal with it, that is how we know. She has lived with drug dealers and did meth with them, and brough her (at the time) one year old son around them. And who nows how many "boyfriends" she had introduced her son to, where he got close to them and liked them, only for them to breakup and the kid never sees him again. My fiance did not introduce me to him until we had been dating over 3 months, meanwhile she would introduce him to guys after "hanging out" with them once. 

But she is still his mother, and he loves her of course and deserves time with her. It was 50/50 for a while there. Then all of a sudden she just stopped keeping him. She would pick him up when she was supposed to, then immediately drive him to her parents house so she could go party or see a guy or just go home and be lazy. He would stay with them every time it was her days, then pick him up and bring him back to my fiance so it looked like he was with her the whole time. Of course, he is close with her parents so he knew. Then it got to the point that she wouldn't even bother, and made them get him themselves. And she would go over to their house when they had him to "visit" with her own kid. Then that even stopped. She got caught up with a POS who got her involved in a robbery. They both got arrested for felonies. Both go bailed out. I think her charges are getting dropped bc she was just the driver. But still. She told everyone they broke up, now we find out they are engaged. And she posts on facebook pics of her hanging out with his teen daughter and stuff. 

Now while all that is going on, she has seen her son twice since a couple months before 2018 started. Once in his birthday, for an hour while he was at her parents house. And another time a month later for 2 hours, where she went and got him from her parents house, without contacting my fiance, and they let her take him for a while. Since then, no contact. Since before the end of 2017 she has contacted my fiance once. It was mother's day. Get this, she asked if her son was going to call her to tell her happy mother's day...he was about to leave for work on a night shift, so he said no he did not have time, but that "mother" is a really loose term for her, since she doesn't act like one. And she didn't ask til 6 in the evening, so it must not have been a priority that day. So anyway, she says okay fine, but that she misses her kid and wants to see him "more" (like she sees him at all...). Fiance says okay fine we will work something out another time when he is not trying to get to work. Guess what? She has not contacted him since. She was feeling sentimental on that one day, mother's day, and expected to be celebrated for something she is not doing? Really b? Really? And after that day, she was over that "sentimental feeling" and returned back to not caring about it or him. We honestly wish she would just leave town and never come back, give us full custody and be done with it. Bc those times she did show up after a long time, she would spoil him with toys and candy, then disappear again for months. Then he is all excited thinking she is the best person ever and comes home bragging about what she bought him (while she was with him for a whole hour, bc that's all she could spare), and doesn't see her again for months. 

Anyway, the point is. It is obviously affecting him. He will go a week or sometimes a month without talking about her. Then one day he won't stop talking about her. We don't shut it down, until he starts to ask when he can go see her, or why he hasn't seen her in forever. We always say she has to work. But that doesn't always slide with him. Then sometimes he will randomly say things like "I'm never going to see my mommy again" or "my heart is cracked bc i don't have a mommy anymore." We just do not know how to respond to those things. She is breaking all of our hearts, my fiance, her own parents and my fiance's parents, and of course, her son's. And then there is me, trying to be all of the things she is supposed to be. Changing my entire life (i used to work and have friends), moving away from my family, becoming a full time stay at home mom (which i do love, i love my time with him), but it should not be like this. He should have time with his bio-mom. She should want to spend time with him more than I want to. But she doesn't. He loves me, and when he gets older he will understand better. 

But for now, we do not know what to say or do. We are sick of changing the subject of her when he brings her up, or making excuses for her. It is exhausting and emotionally painful. I just wish she was a decent person, and actually cared about her child and anyone other than herself. He does not deserve any of this. And I feel like it will get harder on him as he gets older. 

Soooo...anyone have some advice?? Anything is so much appreciated.