How do you deal with loneliness? Not really from not having a SO (although I've been there) but also from not having any/many friends. It's just something I've been dealing with for awhile.
I think... I with certain people like you and I... loneliness will be something that will pop up repeatedly throughout our lifes. I don't say that to discourage hope, however!
Many people question what paul's "thorn in the flesh" actually was... He asked God to take it away over and over... It was likely a physical ailment, but for me loneliness and depression, which often seem to go hand in hand, are far worse than the physical. I've busted up my body... broken my wrist, sprained my ankles, slammed my shins into metal, but the intense, deep, ongoing longing, that hurtful ache, far transcends the pain of any physical ailment.
These things have plagued me for the majority of my adult life... Loneliness and the consequential depression of that loneliness are my "thorns in the flesh". It is that terrible feeling that almost no one truly cares about you, and that you are somehow incompatible with 99.999% of the population... odds that you are not likely to ever overcome in your lifetime.
I'm here to tell you that the first statement (no one caring) is a complete and utter lie formed by, no doubt, satan himself, and that the incompatibility idea, while it might be somewhat truer for some than others, is not so great that one cannot have meaningful friendships.
What I think it ultimately comes down to is a crisis of faith. I have always been a thinker when it comes to the Bible and things... I
KNOW it all to be true, there is
no question in my mind that God's word is divinely inspired, and literally true (even if not all is true literally). That transition from the head to the heart is where the crisis happens. I know it, but if I really, truly believed it in my heart, I wouldn't be telling myself lies about odds and improbability... About incompatibility and helplessness... about lack of self worth of whatever other stupid lie satan plants in my head.
Strive to not just know it, but believe it, to overcome the lies of Satan and know that God is a god of promises, a God who keeps his promises, always. Our lives are not up to chance, but rather, in the hands of a righteous God who can divinely intervene in a daily way, if we are faithful.
Read Nehemiah and Daniel for examples of how God uses one's righteousness to mold and change circumstances, and how the righteous are blessed for it.