Well, you could spend the rest of your life struggling to build up whatever has gone wrong with his self esteem and holding him up and fixing his problems and looking after him…. But then who will look after you?
The main thing that would build up his self esteem is self reliance. He would be better off psychologically getting a breadline job, living in poverty but paying for himself than living in comfort and dreams and relying on you. He has to do it for himself. You can’t do it for him. I understand you want to fix him up but some things you can’t fix for someone else. The best thing you could do for his sake is refuse to support him financially in any way at all. If you do that then he might simply find someone else to keep him, which will be painful for you and unhealthy for him, but at least you will have tried. And at least you will be free to look after yourself and to find someone who will equally look after you and – in future – your family.
Do you want children? You could do it with him, but it will put you through hell because with an undiagnosed, in-denial and irresponsible potential Aspie (or other MH issues) for a father you will have to be solely responsible for the wage-earning and at the same time for the physical and emotional well being of everyone in the family, him and the children. Earlier generations of women in my family have done this and it’s been very unhealthy (OK, disastrous) for everyone, including the children. At 34 you do have time to look elsewhere.
I wouldn’t say there is something wrong with you. But he has obviously always been like this, the signs were there from early on but they didn’t put you off, and he hasn’t improved over time. The need to become more and more engaged with someone who is a bit damaged and keep on trying to “fix him up” instead of backing off and moving on can be self destructive. So if that is a long-term pattern or a repeating pattern in your relationship(s) then it would be worth finding out why and making a real effort to change it. We all have these kinds of patterns, some of us become aware of them and try to change them.
If you were able to discuss his possible ASC (etc) with him, if he were seeking diagnosis and self-management strategies for whatever issues he may have, if he understood that you cannot hold him up forever with him taking no responsibility for himself or for your wellbeing, then OK, that could be a different thing. But now he’s in cloud cuckoo land and you are keeping him there. I am the mother of a (diagnosed) teenaged DS with an ASC and honestly if I died I wouldn’t want you to do with my DS what you are doing with your DP. I’m really sorry. You may have to let him go but then you’ll feel better and in the long run it may turn out better for him too.