Confused decision with close friend

Hey guys, I just joined the forum and I love it. I've been reading some posts and I have a hard question with a problem I'm having with my "bestfriend"

I've known this girl for over 5 years now and since we met we've always been very close. We see each other a few times a week and as of recently things seemed to be changing.
She's been having some pretty hard times, being 7 months pregnant with an unloyal boyfriend who shes been with for around a year. He's cheated on her and although sometimes she's told me he can be a good guy, he's not involved in her or their unborn child's life much at all, and when he's away from her he's treats her like $#%^ and goes behind her back.
Almost everyone in her life including myself and even her boyfriend's friend don't think it's going to last long. or that he'll be around for their child.
Anyhow, recently when we've been seeing each other alot more now and things have started to change. We flirt around and a few times we've talked about dating sometime in the future, if things didn't work out for her current relationship. But we decided to just wait and see what happened. (this was all a few months ago)

But more and more recently I've found myself wanting to be with her. When I'm around her and shes having a hard time, I'm the one there for her to help her through it, not her boyfriend. And I'm glad I am, I just feel like if we were together she would be happier, and thats all I want for her. But I don't know what to do because I dont want to say something if she doesn't want it too.
I also don't want to make things change as friends if she doesn't want this and I'm worried. I want to be with her and the more I seem to hide saying anything to her I feel like it's tearing me apart.

Any opinions or suggestions?

My opinion is to be honest with her. Let her know exactly how you feel. Most likely both of you are sending each other mixed signals because you both want the other to know how you feel. But also, you do not want to loose what you already have. So just talk to her. Encourage her to be honest, that you will be there for her regardless and you be honest as well. She would not be sending those signals out unless she was wondering if you feel the same way about her.