Caught bf cheating, we broke up! Should I forgive him?

[Sandraa]

I'm not those type of girls who check their boyfriend's phone, Facebook, etc. in fact I let him go out with his friends and tell him to have a good time and to text me later. I like giving him his space as I like to have my own space as well. Well I just broke up with my boyfriend because one day I saw two girls text him (didn't read the mssgs just saw the names) so I asked him, and he said they were just friends. I saw his phone and the mssgs were deleted. So that got me curious and so I logged into his Facebook account and omg he was flirting with so many girls talking about "when are we gunna hang out" most of the girls would not reply or be like no, but it was him that kept bugging and asking.
For me that's already cheating if you have to hide or delete messages from your partner. We broke up, but he's blowing up my phone with calls and texts. I do miss him, and he even cried and apologized. We've been together for 2 years and 3 months and he practically knows all my family already. Oh by the way, this is the second time I caught him tryna flirt with girls on Facebook.

The question is.. Should I forgive him? I don't want to but something inside of me is telling me to.. Help! In need of opinions!