First, I’m so very sorry this has happened to you and that you’re hurting so much.
Second,
He told me he only dated her while we broke up to see how he felt about kids because he wanted to be with me so badly (messed up huh?). He also said he didn't feel supported (aka enabled) by me so he turned to her but he can't move on from me and needs closure.
Wow, that’s an All-Timer for the alcohol-enhanced self-pity gobbledygook hall of fame. I don’t even know where to start on how much equine manure that contains.
I have a big concern that he has now burned his bridges with Enabler #2 and she is now threatening to kick him out of her life. Hence, he’s simpering back to you…or at least keeping you hitting the pause button in case he needs another escape route. Please understand that none of what he’s saying is real, useful, or worth the oxygen it takes to express. Ending the call was the right thing to do, so good for you.
I take it you haven’t blocked him? Why? Leaving that door open will just make you live in a constant state of stress, wondering if you’re going to hear from him or not. It’s impossible to heal if you keep giving him headspace to hurt you again. As for “I detached with love which made him believe I don’t care about him,” is just not true. You can’t “make” anybody feel anything, he’s just playing the wounded card because it works.
I hope you’ll consider going back to Al-Anon and maybe finding a therapist for one-on-one support? And please, please, for your own sweet sake, block him. On everything. Until you do, the healing can’t begin.
I’m sorry for your hurt.
P.S.
He told me he only dated her while we broke up
Not even that part is true, is it? Wasn’t he dating both of you at the same time…for months?