How do i leave?

Basically everyone thinks im in a really gun loving engagement but recently things have gotten so bad he has no respect for me, weve paid our deposit for our wedding and it was my dads money. I feel like if i call off the engagement everyone will be shocked and basically talk me back into all the good things about my fiance(which there is many good traits but the respect and constantly lying is killing me) i feel that i would go back to him and i dont want that type of on-off engagement when nobody takes you seriously anymore after? I dont have faith in myself to stay away but i really dont think i can go through with this unless is gets miraculously better asap. Anyone else been in similar situation? I just wanted my fairytale and i genuinely thought i had it until the past two months im devastated i feel this way