Okay well that's a lot of info but at the same time not so much info, so I'm gonna conjectue the hell out of this reply:
Sometimes, people get transactional about things that shouldn't be transactional. For example, you listing the nice things you did or are willing to do for Sam, in an effort to explain why he should really not complain about you needing things from him, could be that. You don't do nice things for people because you expect something back. That's the worst reason to do anything nice, ever.
Also, Sam is allowed to have and communicate his boundaries. If they bother you, that's fine, adjust your expectations and reevaluate your friendship accordingly. But you have to respect them. Someone doesn't say "this again" before a few failed attempts at that.
I also have a suspicion that you feel ghosted when you do not recieve the attention that you think you should. Maybe you are placing unfair expectations on Sam here. He might be busy, or just overwhelmed by how personal you can get, or just prioritize other things in his life now and then. Yes, he saw you miscarry and was there for you at a really dark moment in your life, but that isn't a contract to always be available for all your darkness.
I'm super absolutely not a therapist, but this has some shadows of hyperfixation and might possibly hint at BPD. But as I said, it's really impossible to tell anything with any confidence from posts like this, so take it with a big grain of salt and not at all personal.