I dated a guy like this… He was a bisexual cheater. I was the last to know. The tip off for me was the small bed bit, the excuses, the way you kiss. He doesn’t want you to live with him because then he would be exposed. The guy I dated for almost two years called me every night too but I eventually found out the farce by accident. I was part of a very sick thing and something inside told me there was a problem. Follow your gut.
Sex is very important for men. If he has cut way back he’s getting it somewhere else. If he doesn’t think you kiss hard enough Hello?! He doesn’t like the way you sleep with pj’s? You might just be a front for this guy.
I’d hire a PI and find out what is really going on or move on. After 2 years you should either be moving towards living together and marriage or onto something else. I hope I am wrong but something is wrong and you owe it to yourself to find out. It sounds like he has an excuse for everything but penises don’t lie well.
My mother dated a man for three years only to find out he was a pedophile. I never got a good feeling around him and he drank too much. Someone in his family called my Mother and told her the truth and she dumped him. He was a retired teacher!
Take care of yourself and good luck with your tests.