Met my partner in a MUD, kind of a text-based pre-MMO. He was tank, I was healer, it was meant to be.
In general, talking with people who are doing a thing you are interested in too. The way I see it, maybe 10% of people are “friend” potential, 1% “good friend” potential, and .1% partner potential. You’ll want to look in populations where you have something in common with the people, and thus the odds a bit higher.
Idling at sc, spamming heal all as regen allowed. Good times.