I think the current arrangements are confusing for all of you. Are you separated or not? Separated people don't check in with each other just to chat, generally speaking--not in the "hi, how's your day going" kind of way. But he's over there every evening and sleeps over there often. If he weren't there he wouldn't have any reason to comment on how you are sitting on the bed. No wonder you're all confused.
If I were you I'd seek out a therapist who will get input from both of you. You can tell your husband that you're concerned about changes in behavior, that you're not excluding him from anything. If he's mad, he's mad. Seems like he's upset a lot anyway, regardless of what you do. This is important.