My husband is an A. The cold meds is weird, tho.
I was thinking meth, too. That might explain why he would go for days without taking to you. He may have been "crashing". That is my Hs DOC and when he is getting ready to hit his crash, he is the devil. Aggressive, distant, verbally abusive and just an ahole all the way around. Then will sleep for days. Like 3 or 4 non stop. Its a waste of a wonderful person trapped inside. Waste of a great life he really has, but can't seem to quit feeling sorry for himself long enough to see it.
I hope this is not the case for you. But in any case it sounds like relapse. Hugs to you!