How do you handle a situation like mines baby mama drama?

My fiance has a 13 yr old daughter and I feel like he allows her mother to run our house, things like this is one he pays child support to her, but he only gets to see his daughter when it's convenient for them (daughter/mom), then there goes the daughter use to only come over when we are doing things, and I felt like that wasn't right, but it changed a little. The other issue is that the mother never brings or pick up when she does come to visit us. My issue I have with that is that now that we have 1 income in the house. What is the issue with her meeting us half way especially when we always are usually the ones who come and get her, but instead he makes excuses for his daughter's mom and say well her parents told her she can't go anywhere, but when I go to get her or pick her up she's most of the time is gone. She doesn't have a job. So I don't understand what the problem be. Then when my fiance was working 2 and 3 jobs she still would not meet him knowing good and well he could be very tired. I myself also was working and have 5 children of my own to deal with be tired also. Then again he would say the same thing well we can't make her meet us or she can't go anywhere. Now here is the go getter she makes it her business to stroll through to his job at one point 3 times out the week to visit him at work without his daughter now sometimes she will have his daughter with her, but not often. She always makes it her business to let him know that she's losing weight do he think they could possibly get back together. We've been together for 11 yrs now. And she has not gotten over this situation yet. But he doesn't seem to think it's inappropriate he just says I don't pay her any mind. My argument is you need to put her in her place she's disrespecting you and me. Last issue and concern is my fiance grand mother is very ill and his daughter's mom calls to him to ask all these questions about his grandmother, now what bothers me is that 1 he really didn't see his grandmother much due to him working a lot, 2 thing is after he tells her the situation, she begins to send him texts asking if he needed anything is there anything she can do. My concern was why in the he** isn't she asking your mother this. She has yet to ask your mother anything about her mother. The one who she needs to be asking, but she doesn't. And thinks it's okay. Like I told him before it's just anything to hear his voice and or just to keep you in her present. I also forgot to tell you that yes she's is still in love with him and the reason I know this is because she's told me before and told him. So he knows and all I ask is that he put his foot down and stop leading her on by allowing her to control him and he makes excuses for her. I think he doesn't say anything because she may refuse him to see his daughter like I told him you already pay child support, so if it boils down to it you shall take it through the courts and let them deal with it cause if the shoe was on the other foot she would have your *** in court. So what should I/he do in this case or what do you think.