Ex wants to be friends with me? LONG

I was in a relationship with this guy ((Let's call him M.)) for three years, and we broke up about a year ago the day after I had my son. We always had a really good relationship, never fought, but had a few arguments. When I found out I was pregnant, I decided to adopt my son out because we were both young, ((I was 19, he had turned 18 the day before.)) jobless, and living with our parents. The baby was unexpected, as we were using birth control. We had disagreements about adoption our son out. He and his father wanted to keep the baby, ((His father because he never got to raise his M when he was a baby. All the drinking, pot smoking, and medical conditions he was couldn't POSSIBLY be a reason for this.)) and my mother did as well, until she realized that she only wanted her grandson for a selfish reason, and decided to have my back in this. However, M never said much about the subject. He went with me to dinner to meet the adoptive family, and never rejected the thought or conversations about adoption. However, after having my son, he coerced me into signing a document confirming him as the father, and stopped the adoption just as the family was about to take our son home. Afterwards, to make this long story shorter, he broke up with me and tried to take custody of our son, claiming that I never wanted him. It was a huge mess of drama, fights, cops being called on M's father ((Who in all honesty, had NO business in this situation.)) lies and a lot of pain on my part, because for the longest time, I still had feelings for M. In October, after family issues left me displaced and homeless for two weeks, the time of which our son spent the entire time with M ((M ended up settling for joint custody, but it's split about 40-60, with me being the primary custodian)) At that point, I spent a few days with him, and we sort of patched things up, but afterwards, when things were settled and I had a home, he freaked out when I was able to take my son back. If he could have legally stopped me, he probably would have- he threw that big of a conniption- so things went back to being bad, and I decided to move on with my life. Since then things have been neutral between us. No conversations, and very little interaction. I make it a point to pay him as little mind as possible, and keep my attention on my son, even when we're talking. This is a habit from back when I still had feelings for him. Half the time, if I looked him in the eye, I would end up closing the door and crying for an hour afterwards.

Come here in December, I got a new boyfriend, and have been posting about us here and there on Facebook, in which M and I are still friends, so we can have another means of contact. ((Might I also add that M has had two girlfriends since our break up and is currently in a relationship.)) The day after that post, after conversation, he comes to the door and states that we need to have a talk so, and I quote "We can have a stable and less fragile... thing.", and left because he couldn't stay to actually talk. M was very friendly after this, and always tried to talk with me in the brief moments we would see each other., However, he never made a mention of talking afterwards, but I wasn't exactly sure on what needed to be "fixed", and wasn't too keen on talking to him anyways. Turns out that yesterday, we had another fight after I went upstate to see my boyfriend.

The whole point of this post is: Should I try and stay friends with him, even if it's just for our son, or should I just say smurf it, and keep things the way they are?

Hell no. Any man that EVER thought it was ok to take my kid from me could remain under the title 'babys daddy' lol

I think if you can both be civil and remain on good terms for your child that is good enough. I guess it kind of depends on what he means by friends. Because if he means he wants to be more open to communication, I think that is great. But if he really wants to be besties or something, I think that probably isn't the best idea.

I'd try to distance myself as much as I could if I were you. It would be great if you two could be civil for your son, but for your own sanity I'd keep a healthy barrier between being civil and being "friends." That's just considering your past. But then again, it's all up to you.

-In reply to everyone-

Things have been civil ever since November, so I'm not sure exactly what he thinks needs to be "fixed". I have a feeling he might be a bit jealous, but I'm not sure. He was never "possessive" when we were dating, but he did say he would get jealous very easily.
I just never expected to get a boyfriend this fast, and apparently, neither did he.

Buuuuuuut, that's just a thought.