In Lovery With My Best Friend

I have spent the past year an a half of my life living with my best friend. I've known her for eleven years and originally met her as my close friend's girlfriend. They have since divorced and one of the nasty side effects of the divorce became the loss of my friendship with him and our circle of friends due to the fact that I refused to take a side. I had feelings for her at the time but had no intentions of pursuing them. About a year and a half after their divorce, when it became clear my friendships with him and our circle of friends had truly dissolved, I chose to pursue her. Everything was muddied by her (and my) drug abuse at the time. I have since gotten clean and helped her do the same. We fooled around a few times during the darkest times of our drug use, which resulted in a very poor outcome due to my guilt in getting involved with her sexually when she was not of sound mind and my inability to perform adequately under the influence. She ended up pregnant with another man's baby, and lost her job and I have since been caring for her. I am deeply in love with her and want nothing more than to be with her. The very least I want is to be given a chance to try to be together now that we're both clean and doing well, but she's constantly keeping me at arm's length. There has to be a way. Please help.