Controversial answer here, but I read "The Game" by Neil Strauss and then "The Mystery Method."

Cringey as fuck, but it did stop me being bitter towards women and realise that the problem was me, not them, and it stopped me elevating women to the level of goddesses in my mind.

I never went deep into "game" but I read some basic stuff that changed my outlook on women and life and it made a dramatic difference to my love life.

As a general rule, I think a lot of PUA stuff is kind of gross and makes me uncomfortable now, but you have to understand that to a guy who had a sheltered upbringing and had NO CLUE how to attract women, there were some valid ideas in there that really blew my mind.

It does seem to attract a lot of bitter men, and it makes it very red pill-y and unpleasant these days but it did alter my attitude to one of "women don't owe you shit just because you're nice, be pleasant to everybody who deserves it." Although it's easy to see how it can breed very unhealthy attitudes.