Should I believe him or always keep my guard up?

[Belovedcar285]

in 2011 when I was 17, and he was 16 I met a guy who i fell head over heals for.. the 2 months we dated he accused me of everything and he even cheated on me. We broke up and since 2011 we've talked a few times about getting back together but I always ended up finding out he was going behind my back and talking to other girls and accusing me of more things I never do. one time during 2012 when he re-activated his facebook it was the exact same time his ex unblocked me and it was during the time they got back together. (she blocked me because he started a bunch of shiz between us so she blocks and unblocks me all the time) i bring this up because me and him have been talking again after a few months of no contact and he seems to have really matured and changed but i just found out yesterday that he re-activated his facebook and she happen to unblock me again.. I dont know if that means the same thing it did before but just a few days ago he said he wanted to get back together now he's saying he wants to wait. so i dont know if i should just give him the boot or try and see if it will work this time???
am i just being paranoid or is this a major red flag considering it's the same ex???

[ShyGirl2]

Stop wasting your valuable time ; Give him the boot and don't look back , I am sure that you deserve better

[devonian Rodders]

Give him the boot. To much of a coincidence he and she unblocking you on FB.
Someone like him accusing you of things he does is just to shield his own guilt.
There is also a saying "A leoprad never loses his spots" which might apply to him. meaning he will never change !