My mother & sister won't speak to me because they hate my boyfriend, what will I do?

I have been with him for a year & a half and I am 17. I really care about him and he is good to me. He was texting a girl behind my back I freaked out & excused him of flirting with her. He was whatsapping her and he deleted their chat, my parents made me break up with him. But i didn't want to so behind their back i told my bf that I'll get back with him if he could restore the whatsapp msgs so he did & the girl kept whatsapping him and he would reply but bkuntly so thus he was flirting with him. So we got back together. My mum thinks he's 'sly' and 'ugly' :s but my friends all like him. Ny mum also hate him because one night i was so drunk, i slapped my bf in the face :( i kept screaming at him & he put his hand over my mouth to stop me from screaming. Another girl saw & accused him of 'punching me in the face' but because I was so drunk I believed her and I rang my sis saying 'he hit me'. The girl told my parents and they believed her. ANYWAY.. I know he didn't punch me as I remember that night!!! And now my mum hates him but my dad knows he didn't hit me and i know! I was so f*cking stupid that night.. Anyway i sound like an a$$hole! Anyhoo, I have been seeing him behind everyones back & i got caught seeing him today!! My mum said she wants nothing to do with me!! And my family won't talk to.me! What will I do? It's so awkward at home i feel suicidal :(