Relationship in crisis because of his crazy kid
I've dated this guy for over half a year now. He is a very nice and caring person. We have similar views on many things and get along pretty well. One thing that concerns me is his daughter who turned 18 last year. It seems like ever since she turned 18, she started making stupid decisions on after another. She could have gone to a very good college with military scholarship, but she decided to quit. When this spring semester started, she even quit high school when she is only a few months away from getting her diploma. And she had been doing well at school academically and socially. (There was other crazy stuff that she had done, but I'll just omit them for now.) Last weekend I was told that she was 8 weeks pregnant. What's even worse is her boyfriend's parents didn't even care and kicked the boy out of their home. Now she and her boyfriend are both living with my boyfriend with an unborn baby.
My boyfriend is a single father who had very bad relationships and divorces. He is not rich either. In fact, he works on an hourly wage. Hearing this news made me shocked and angry because I can't understand why someone would want to get pregnant when she even can't support herself. I think she actually got pregnant intentionally: she had been on birth control and decided to stop doing it last December. I'm also angry because I hate people who never think about others. In this case, his father, my boyfriend is working hard to raise them (he also has a 14 year old boy from another marriage living with him), she not only didn't help with house work, but also kept causing troubles, and they are not small troubles.
My concern is that if this girl will ever grow into a reasonable person and stand on her own feet. So far, I haven't been convinced that this girl will ever be able to or want to be independent. But I might be wrong. I like this guy, but given his financial situation, I don't feel secure, financially and emotionally. This girl and her craziness or stupidity is like a time bomb. My question is am I over-thinking? Will this girl ever change? Will she stop making troubles like this? Is there anything we can do to keep our relationship or should I just leave?
I appreciate your suggestions or comments.