Not all combinations of individuals “works”. Besides the possibility of learning from a bad experience, it could simply have been some incompatibility between two people and now in this case your ex is presumably in a compatible relationship. … OP, it almost never pays to follow an ex. It is far more likely to upset you than confirm your previous opinion. And on social media or even in person, people generally try to present their best side to the public and friends. … I think that it’s relatively rare that when a relationship breaks down that it’s one person’s fault. Life is complicated and so are relationships.

You don't know what their relationship looks like on the inside. Did everyone know he physically and emotionally abused you, or did you hide it and pretend everything was good?

You were not the problem. Something seems to have caused him to change, but no one can say if it will last. Successfully getting away from a monster makes you a warrior. And if you haven't found your true other half yet there's no need to rush.