I'm with Monica geller on this
"I don’t believe in soulmates, and I don’t think that you & I were destined to end up together. What I do believe is that we fell in love & that we work hard for our relationship."
I don't believe there is "the one" or "soulmates" I believe there's physical attraction initially, that with time if you have enough in common and similar values develops into love and that you work together to keep the relationship successful when one or both of you is having a tough time for whatever reason (exceptions of infidelity, abuse & extreme illegal behaviour of course).
I'm a divorcee myself (very intense relationship from both sides but after I had dd I suspect my not being 'all about him' any more wasn't something he could cope with and instead of talking to me he had an affair), but I haven't given up hope, though I'm fine single for now. I'm basing that not only on my own relationships but also the successful relationships of others I've observed.
They all are mutually respectful, thoughtful and supportive, but also they work on things like making time just for each other (the cringey phrase "date night" comes to mind but the spirit of this is important), appreciating each other - and fun!
I suspect you're "looking too hard" and possibly only considering those that "tick all my boxes". Don't write someone off because they are short, have a job you consider unattractive in some way, have a "weird" hobby... In brief are "not my type" your way hasn't worked so far so try something else. Maybe you're wrong about who your "type" is. Makes me think of Charlotte in sex & the city - trey was "perfect" on paper but a disaster in reality, whereas Harry is actually perfect for her - but she almost loses him by allowing her snobbery over the "perfect man" to distract her from her true feelings.
The only other thing I think may be a factor is if you're in denial over your sexuality? I only say this as I know a few gay friends who've said similar then when they finally accepted their sexuality - butterflies galore!
I agree mistresses post was misconstrued.
To maximise the chances of meeting the right person you need to have variety in your life both in what you do and who you know. I've known couples who've met in the most unlikely circumstances who wouldn't have if either party had gone "nah don't fancy doing that activity/going to that place" when they'd never tried it. One couple I know met as they'd both been dragged along to a concert by friends of an artist neither could stand! They still don't like the artist musically but accept their (unwitting) part in bringing them together so that it's a bit of an in joke for them now.
OLD has its place but I think a lot of people wrote off potential people on OLD because they score a negative mark on a factor in their mental list of their "perfect" partner, well nobody's perfect.