I am sorry you are here. What a mess. ... Sadly, I do think you need to treat this the same as an affair. It very much sounds like it is, bio mom, or not. 150-250 texts a day, hurriedly wanting a D, planning to move in with her after just meeting her -- this is the same psychology as an A (the limerance, obsession and addiction), whether it is s-xual in nature or not. Please listen to these guys, they truly want to help you. ...
I think it was you that said that this is a documented phenomena -- a strong attraction/pull between a parent and bio child reuniting in adulthood. I can speak to this as well. Others here describe it as creepy and disturbing and I think that's because most people just cannot relate. It makes us uncomfortable. It took me some time to understand it too.
I do know that it happens though and know a sitch (friend of a close friend of mine) very similar to what you are describing. It resulted in a full blown romantic and s-xual relationship. They were completely obsessed with one another and even described it as feeling like a strong force of nature. My friend herself was very understanding because she belonged to many adoption groups herself and longed to have known her own bio father. Through her groups (she was involved in many) she came to see this type of R evolve more than once. It took me some time to understand it myself, but that is only because I cannot relate.
Of course I have no idea what the R is between your H and his mother. What you are describing tho is in many ways similar to the rest of us and he is in the fog and deep in limerance. Sadly, your only option right now is to let go. In time, the intensity and drama will subside, and it is very, very unlikely that they will have any long term romantic R. What the posters are telling you is that you cannot make him see the light, force him into reality, or convince him to give you another chance. Only time can do that. Spend the time apart taking care of yourself and becoming the best version of yourself that you can. It is very likely that down the road -- as his fog lifts -- he will look back over his shoulder.
Take care, Blu
“Forgiveness liberates the soul. It removes fear. That is why it is such a powerful weapon.” – Nelson Mandela