Mishka - Bworl posted a very wise post on TOH thread [about two posts back on her thread] about doing what is right FOR YOU in all this mess.
On the positive side you did something different. You had a few beers, and were a bit flirty. Good. You survived, and dealt with an interaction in a positive way. Good. It broke you up, but you didn't show it. Good.
You hurt, not so good [for you]. I undertand, We are all torn between wanting to see the loved one, and being hurt by the changes in them. Do what is right for you, remembering that he is NOT himself right now, and will not be for quite some time.
Your personal sitch is hard I know, and that drags you down. But perhaps these interactions are best avoided? This MLC stuff may go on for a while, and if the interactions are reduced you will expost yourself to less pain Do not worry about your h 'forgetting' you. I posted about convos with two older men who spoke of their abiding love for wives who had left them 20+ years ago. He is out of it now, but will not be for ever, but in the meantime you have to go on living, hard as it is. For youerself, for your son and your mother. There were many tmes when I wanted to die of grief, but gradually it gets better, and now I am truly grateful for life, even though my h is as far away and madder than ever. And he is a real spewer. The thought of a civil text from him, let alone a kindly one, makes my head spin.