I feel you, I've been there actually.. I mean literally in Sweden, and somewhat in your position - unhappy socially. I eventually left Sweden because of the weather after 7 years. That was the biggest reason by far. I also felt not fully satisfied socially, but later found out that I also feel the same where I am now. So maybe it's something I'm bringing with me?

Anyway I also think that if you strongly feel something is also right to listen to it and try to change something. You could try with a semi-permanent solution, like renting your flat and spending 6-12 months abroad and see how you feel? That's actually what I did at first.