Hello! For the sake of clarity I just want to say that what I'm going to write is MY experience - so it may not be the same for you.
When I've been feeling very frustrated/lonely or needy, focussing in on that and trying to 'solve' it hasn't worked too well - the main result has been making me very focused on 'the problem'.
Personally I've very seldom, if ever met kink play or sexual partners on line. I've made LOADS of friends, but I seem to be the sort of person who needs to get a sense of chemistry in person. That might be the most brief meeting, from there often lots of conversation has taken place on line, but I need to see, sense, smell..whatever...to really get a sense of chemistry.
Speaking of chemistry - some will disagree - but I don't always limit my play to only those I feel the sizzle of chemistry with, which has helped majorly with the 'frustration' aspect.
I've played with people who are bloody well charming and polite, who make good conversation, who treat me with respect, who seem to be well integrated into and taking part in building their kinky community, who offer skill sets or good matches for kinds of play I like. Sometimes this can feel clunky or awkward at the beginning of a scene, some times not! Many times I've realised chemistry isn't everything. Often the ability to form deeper connections has grown overtime. I've made some solid perve friendships, some good kinky friends with benefits relationships, I've played A LOT.
It might also be that I'm a bit suspicious of what I perceive as chemistry... I look back with the gift of hindsight at some connections and think 'oops, maybe that was more like the sizzle of my fragile ego being reflected back at me via approval'.

With finding people: go to events, go to parties, munches, conferences, workshops. Learn skills, having skills to offer is damn handy!! Know what you are into so you can tell other people, I'm NOT a big technical player, but I AM a dynamic player.
Do service in the community by helping to organise stuff. If the event you want is not there, then think about making it happen yourself. IF you have any desire to get out on stage *ahem* ...I have to say this will do your sex/play life no.harm.whatsoever.
And above all else DO OTHER THINGS, there is a huge life out there .... kink (or whatever intense issue I choose to stare at on any given day) is but one aspect.