It's tough to say if this relationship is worth pursuing. He's done so much damage that the relationship has kind of lost alot of it's potential. Wouldn't you agree? Does it feel as special and as good as it did when you first started dating fresh? I know he messed shit up then too, but if it's much to soon to start dating (even after 7 months) alot of the hurt feelings are still there.
It doesn't sound like you have alot of faith in this, rightfully so. You are embarrassed to even mention you are dating him (I caved in, AGAIN!), and your friends are tired of seeing you hurt. What I don't like about this is that he came to you out of the blue mentioning how much he loved you and missed you and everything. I think it's a huge red flag to come at you with all this need all of the sudden and trying to play upon any feelings you still have left for him. Can you really go from not talking for 7 months to back together in one meeting? He NEEDS you because he's alone and doesn't want to be that way, and not even if you feel the same way or not. Your feelings are irrelevant, that's the scary part. He hasn't changed from the person that he was before because he's too busy looking out for his own self interests, and logically getting back together with the same person that he was before can only mean that you will break up again.
By all means if you are really truly "together happily for 2 months", then try and see where this thing goes. If you already are having doubts (coming on to this forum before you guys are on the skids again), that can't be a good sign. Just know that you are entirely responsible for the situation that you put yourself into and are in no way a victim if he ends up hurting you again. It would be entirely on you. You are only worth as much as you allow yourself to be treated as.
Maybe you haven't met somebody else in your time you guys were apart, maybe you were still obsessed with him on your mind. But if things aren't working out with him, remember that he is not the only guy on this planet that you can be with and make you happy. It's difficult when you still care about somebody to meet other people, let other people in, or give them a fair chance. But don't be afraid of what else is out there. You are perfectly capable of having a healthy relationship with somebody that isn't already a proven failure. A fresh start, the magic and excitement you felt the first time with somebody new. And with your experience, you can choose somebody more worthy.
Waking up next to a beautiful girl,
Step outside and say hello to my beautiful world.