Broke up after 6years...help.

So my fiancé and I just broke up yesterday. We've been together 6yrs in September. We were supposed to get married this October. Anyway, I found out he was cheating on me... aside from tht I just wasn't fully happy anymore. He was so different. But I loved him and still love him so I tried to make it work. He knew how I felt for months. He never did anything to change. Also, he wouldn't grow up either.. wanted to stay in his mom's house and constantly doing things a MAN wouldn't do. Anyway, I left and moved back in with my dad. But I'm beyond devastated, heart broken, pissed off, and confused... what do I do? Please help.