That's actually what I'd suggested if @Tsukkin care enough to go through trouble. Get another friend to introduce to him so he can go bother someone else.
Tsukinn, Instead of antisocial, you sound more of an introvert. If you were actually antisocial you wouldn't have met up with him even if he's an old friend. Just tell him socializing takes a lot of energy for you as an introvert and constant attention is draining. Unlike 85% of the population who are extroverts. Meeting up once a month or two is fine, but more is too much. texting all the time is a pass time for extroverts who need the attention and validation. You don't have those needs. A convo is fine every now and then, not every day. Your his friend, not his girlfriend. Friend zone is a thing for a reason. Got problems? Got a friend. Want something more? Sorry, your a friend. Some friends would die for each other, but you two aren't that close, and haven't been close friends for two years. Just tell him he needs to slow his roll, it's stressing you out. You'll have to lay things out to him and work on a compromise that will work for you both. If you can't, it may be better to cut him off. As disparity between two people's boundaries will eventually cause conflict. Initially feeling bad is better than bottling feelings up till you blow up and say something you regret. PS: No matter the type, a relationship of equals always ends when one wants more than the other is happy to give. At that point, it changes to a host and parasite or master and slave relationship. You can't be equals if either of you are afraid to tell the other what's on your mind. PPS: Loyalty is nice, but people change, and their goals change. Relationships come and go because of this. To not accept change(in the guys' case), or to not communicate change in desires(in your case), will just lead to more pain as time goes on if the situation isn't rectified.
I totally get you. Especially in the colder months, I don't want to see anyone at all. Once I honestly asked my friends to "not invite me out between November and March" and they still ask me if I'm hibernating or something. As for the guy... I get the feeling that he isn't one to read between lines. People like that tend to understand things in a way that is favorable to them. So your "haha" (please stop) might sound like a "haha" (that's funny) in his ears. In that case, throwing hints will do nothing at all and your best bet is to just ask him what is up and why did he suddenly started to chat with you. You could start from mentioning the fact that you weren't in contact much and try to find out why did that change. But whatever you do, don't do anything that you don't feel like doing. If you feel that it's wrong, then most probably it is. Anyway, good luck!
As a man, I would not understand if you're not brutally direct about it. So go for something like "Sorry, but I feel awkward talking with you and would like to spend more time with my hobbies, and you should also prioritize your girlfriend more before you do irredeemable damage." Also, not wanting to see people in a long time is understandable to me; I hang out with my probably one last close non-relative friend maybe twice a year. And some other close friends maybe once in year(s). I don't understand why not talking for a time would change my positive/negative impression of anyone. I mean, there's simply just nothing to talk about.
Just be straight forward and tell him you're not comfortable hanging out when he has a serious gf try seeing what would happen if you invite both them out together you'll see his intentions quickly
If this guy is really up to no good, be ready for some very negative comments thrown at you. For this I recommend blocking the person. You most likely won't have something like this happen to you, but this is my suggestion just on case.