Family hates SO, TTC

ayoungechrist, • 21 year old artist pregnant with my first :)
My SO and I have been trying to conceive. My family absolutely hates him because we have had a very rocky past due to my bipolar disorder and our history with drug addiction, but honestly they hated him right off the bat because he comes from a less wealthy family and does not have everything handed to him as I have. We have overcome our problems because of how much we love each other and want to have a future, and he has been saving for an engagement ring for the end of this year. I can finally say that we are healthy and happy together and I feel so saddened by the fact that my family would literally alienate me if they were to know that we are still together. My mother has told me that she would make sure that every family member (I have a HUGE family) would not help me with anything or allow him around, that even if we had a child she would not be a part of his/her/our life. I've already gotten a taste of this solitude while I was in my first year of college before we broke up for a short period of time, I was not allowed in the house or to see my siblings. It is very discouraging because I have always been family oriented. I want to start my own family but I don't want to lose mine in the process. Thoughts? Suggestions on how to break it to her once we have conceived? (if it's possible, my doctor told me I will have difficulty, which is why we have been trying while I'm still younger)