if uou have both learned from past mistakes and know now how to prevent this in the future and find a better way to resolve conflict-then i dont see the harm in trying again. just be mindful of where you went wrong last time and if you see any red flags that all that crap will start again then get out quick with no more chances.
the biggest issue is lack of trust. has he gotten over that and his insecurity? being accused of something you havnt done repeatedly is emotionally draining and over time can shatter your self-esteem so dont put up with that. also are you 100% sure you can trust him? people who have this crazy paranoia can sometimes indicate that they are the one cheating.
many couples get back together. for some it works, for others it doesnt. you need to take back the stuff you said to your friends. you cant expect them to like a guy who you have done nothing but b**ch about. tell them you would appreciate their support and no "i told you so" if it doesnt work out. tell them you both messed up but he wasnt as bad as you made him out to be-you were just venting and you want them to give him a chance.
hopefully you are both more mature now and can try to build a healthy foundation. if you are starting again-leave the past in the psst. no fighting over something he said a year ago. its a fresh start.
"Don't ask a question if you can't handle the answer".