failed at giving that baby a better chance at life

so I just want to rant about something that's been bothering me. almost a year ago my fiance ex wife was arrested and facing many years in prison. a lady from the daycare had her 2 year old daughter for a few months . once we found out what was going on I spoke to my fiance since we have failed at trying to conceive for years I wanted to adopt the little girl. everything was going so great until she got out of jail and didn't get any prison time only probation. she was out for 2 months before trying to see her daughter . and I also have her son whose father is my fiance.she refused to help with daycare cost . couldn't help get the kids to school/daycare on the regular since we both work 15 hours a day most of the year with the exception of 3 months off. and when she would help the kids would be late. or the day care would call saying the baby is to sick to be there , when I asked her only to watch her a few hours till I could leave work early. I invited her to the kids birthdays , rented bounce houses etc she never called or came over. also invited her to thanksgiving with no sign of her. around Halloween she wanted to see the baby although I didn't want her to I couldn't stop her, however I was not letting our son stay with her because she doesn't have a stable home and loves to party & do drugs. well I tried to pick the baby up that evening with no response to my calls I went by where she was staying at the time and she wasn't there . she had the baby about a week and on Halloween I asked if I could take them trick or treating she said yes cause she had plans & didn't hear from her for about 3 weeks. when she just showed up unannounced and come and took the baby . she had her for 2 weeks. when she came to see her son the baby wouldn't have anything to do with me said she's only nice to Jessica ( Anonymous name for the baby's mom) she has always called me mom and her by her name even though at first I tried to correct her I could tell it upset her. so then she asked if I could keep the baby for awhile and I said yes but I need her help with daycare cost or for her watch the baby while I work all week.she then tells me she's leaving town to go see her man out of town working and I say look I'm not a baby sitter, I did all of this wanting to provide a better life for the baby and adopt her , not to be a sitter when you don't want to play mommy any more. so I either want to go forward with adoption or I have to step back because it's breaking my heart.she then asks for clothes because she didn't have much for her because she only worked for 2 weeks to pay her lawyer when she got out of jail.so I packed up all (about 200) clothing items I had purchased for the baby. told her I have a bed and a room full of toys she can take too & she says she can't cause she doesn't have a place for them. .... I just don't understand why she can't stop partying and be a god mom or allow her child a better life with me.now I'm left so heartbroken. I kinda wish I would've told children services I wanted no part of it. but I fell in love with the little girl and wanted to bust my but to make her happy and well taken care of....rant over/heart broke