Need help !

I recently found out I am pregnant. In the past my boyfriend and I have spoke about pregnancy. He does NOT want anymore kids because he has two that are teens. He said if I were to get pregnant I have to get an abortion. My boyfriend is 12 years older than me and raised his kids completely alone. I am afraid to tell him cause I do not believe in abortion when you knew the potential results of unprotected sex. What should I do and when should I tell him!?