Oh, and letitend - I am sure you have read this elsewhere, because I need to tell myself this as well at times, too.
It's so hard to think of our ex's with another and it also feels unfair when we see them happy or with our "replacement", etc. That's why everyone here encourages the No Contact rule and I firmly believe in that especially because I don't want to know who she is dating or what she is up to as far as relationship goes.
Part of that is our jealousy, part of that also is I think because deep down we know that it means they are not changing or looking to get better, they are just looking to "keep the party going" or "start over" having learned nothing. It would sort of be like if you left an alcoholic, then a week later, started dating another alcoholic!
The more I think about it, the idea of her dating someone else doesn't make me as sad as the thought of what her, and that someone else, might be going through as far as a repeat of our past. All the negative things I mentioned in my first post above, are about to get revisited onto someone new. And probably even worse than that due to the progression.
So, in hindsight, it doesn't make a lot of sense to feel jealous, but maybe just sad because you'd had hoped they would turn it around and seek out recovery. But as we all know, only they know when they are ready for that, if ever.
You will be good! If I could recommend anything though it would be to avoid knowing as much about his new relationship and life as you can, just to protect yourself and stay focused on what makes YOU awesome.