He Left Me…Had A Baby…Should I Take Him Back?

Hey family, I met and started dating a guy in 2010 after moving to a new city. We were together for about 6 months and days before our “anniversary” he drops the bomb through text ( how appropriate)that he is moving back to Virginia because “some girl” was pregnant. Well that some girl turned out to be an ex that he was still sleeping with and apparently unprotected because she became pregnant with his child. Being a daughter of the fatherless tribe I would never EVER condon any man , mine or not to abandon his child and responsibilities to be with me or any other woman so I told him she deserved him and that they would make a great family along with a few expletives and other colorful words. For obvious reason I was devastated but eventually got over the ordeal and moved on. Sooo Here it is four years later and he sends me a message on facebook. He said he had something he wanted to say so I gave him permission to call and he apologized and went on and on about how he missed me and how everyone pretty much told him he was stupid for effing up a good situation and how it took him leaving to realize how he messed up and moreover how he really broke my heart. The thing is we were both fairly young ( 19 and 20) not that immaturity is an excuse but nevertheless I’m appreciative that his immaturity was revealed before I invested more feelings into him. I wont make excuses for him because of how the situation went down and the total disregard for my feeling or our relationship, however i cant ignore what we used to have. I don’t want to be thirsty 😉 but I don’t want to be the type of person that can move on but can’t forgive and trust. He contends that he still loves me and wants to eventually marry me and have a family with me but at this point I can’t trust that brutha as far as I can throw him. I can’t shake the phrase ” once a cheater always a cheater” and the fact that some men feel like a baby mama is a lifetime “fallback” . I refuse to join a “league of baby mamas” as I know I deserve more than that but I also recognize that people grow and evolve, I guess it’s matter of patience to see if he serious or not. My question is one am I being thirsty for even considering that I might one day take back a man that had a baby on me, and or should he even be given another chance. At this point I want to safe guard my heart and I don’t want to be made a fool, but the love was never lost… HELP Y’ALL!!!
Sincerely dazed and confused