need relationship advice

So my boyfriend and I have been dating for 8 months and we are always off and on due to constant fighting and lieing. Anyway so this time is supposed to be our last time, we currently aren't dating but working things out, he's made me feel like shit and I have sometimes done the same. I talked to my best friend about it and she said if I get back together with him she won't be friends with me. Should I try to be just friends with my ex or leave him completely? Really don't know what to do