“I’m not happy, and I haven’t been happy for awhile, and there is NOTHING you can do about it” sounds a lot like the first warnings of a guy who is planning to leave to be with someone else. I see Xantippe said the same thing. Yes, he skyped you, but was he also skyping someone else, too? More suspicious is his instructing you not to meet him for his homecoming. Why not?? I cannot think of any good reason to draw that line - I can only think of the nefarious reason.
It sounds to me like you need to find out what he is doing these days. Staying home and crying about you-don’t-know-what isn’t doing you any good at all. The truth may be something to cry about, so maybe find it out and get it over with. Do you not drive, maybe? Is he staying in your home, and you are with your parents? Because if you do drive, you should just drop in. If you don’t drive, maybe your Mom, your Dad, or a friend will help you get there and find out what is going on. Seems likely there woudl be a sympathetic girlfriend around to support you in this.
Sometimes people cheat. There is a lot of support for cheaters these days in this culture that venerates the sacred “Whatever makes you happy!”. Some people won’t cheat no matter the difficulty they are in, because that’s the kind of person they are. I am sure you know what kind of person you are. But do you know what kind of person your husband is?
Just know this: When cheaters cheat, its NOT a reflection on their spouse, but its a testament to who they really are. And who a person “really is” is something a spouse has no jurisdiction over.
The truth will set you free, even if its an unhappy one. I hope its not an unhappy truth you are facing, but know that the truth frees, nonetheless.
(I don’t know what mental issues you were dealing with, but, giving your love and trust to someone who is not worthy of that trust - or is abusing or manipulating it - is a “crazy-making” situation. Sometimes mental health conditions are* situational,* rather than innate.
Whatever this situation amounts to, God can sustain you and you can trust Him and He will never let you down for any trust you give Him. You cannot outgive God. He desires that you put your trust in Him. Give Him your trust, and He will not let you down! He can hold you up, even in the midst of a ruinous situation.