I think maybe a paranoid disorder then? No, he isn't involved in any illegal activities. He has a mundane job and a mundane home. We know no one who would bother to hack into a phone and send two text messages.
I am leaning towards this is an elaborate overreaction in his mind. He draws conclusions and thinks things that just aren't accurate.
I think the pot smoking comment may have been a back logged message along with the "Maybe I need pills too". It's possible he was intoxicated last night and tried to send messages that just sent over now. I took them as him mocking me for returning to taking celexa for my issues.
I truly believe he isn't lying, and he thinks he was hacked. He just draws the worst conclusions from everything.