I played Guild Wars for years, and had to set up a full AI team to help me conquer the zones one by one because nobody else would play with me for more than a super rare single session... and I only did PvE because PvP isn't fun. The only way I could play with others was by helping newbies... but eventually I stopped playing because a particularly idiotic newbie got my Survivor character killed just before getting the second tier title.... and when I asked why they were behaving so recklessly, they replied "its just a game lol"... At that point I would gladly have chopped them into slices from the toes upwards and rubbed the bleeding stumps in road grit every step of the way...
... But instead I changed over to Mabinogi... and I played on the American Tarlach server which had just started because there weren't any European servers at the time (those came later).... At least everyone could understand me there, unlike the European servers for Guild Wars... but 90% of the people I encountered more than once were only interested in sitting around in Tir Chonaill and chatting. Besides that I got the same issues as Guild Wars: Everyone was just sticking to their own cliques and I had no in.... and the randoms were completely useless. More of a liability than simply learning to solo.
In the end I spent several years just soloing Mabinogi, which happens to be a rather unforgiving and brutal MMO for solo players. I actually ended up pretty damned good at it to the point where for a while people actually recognised me on the server... not that they ever played with me. BUT eventually I took a break from the game and in my absence it moved on, and I was no longer one of the best melee fighters on the server once I got back... so I lost motivation even more... until I eventually gave up and quit.
Between the two games, I was playing for the better part of a decade and never once got any friends to play with.
I had to give up in the end. My experience had left me severely jaded and utterly resentful of MMOs, so I promised myself I would never play one again.