Why We Have Our Parents

I have spent many years learning about our spiritual selves and realize we all chose to reincarnate at some particular time to an exact set of parents in order to work through things in this lifetime so we can better evolve and move on and not have to go through this again and again and eventually become one with the universe. At least, that is my interpretation of life and spirituality. Do you agree? My question is why did I chose to have an alcoholic family around me and a mother that is selfish and forgive me, but sick in her mind? It has made my life and memories very hurtful. I have forged an almost normal life for myself but have never married. I am successful in my job, am financially steady, have friends, but there are some things missing. I am not sure how to even talk with her in that she is always drunk when I talk to her. Should I try the intervention approach? She lives in a different state 4 hrs. from me (on purpose, actually). My father died 3 yrs. ago on Christmas Eve when he was home on hospice care and she threw my brother and me out of the house and we had to stay with a neighbor for the night. What is your recommendation for healing through all this? I realize you are inundated with letters and emails, but if you will answer me, it just might make a difference.