The preventative measure against falling into the despair and bitterness of incel theory is having lots of women who are regular friends in your life. I am irredeemably bad at getting close to any attractive woman and have been treated indifferently by those I was dumb enough to ask out when I wasn’t right for them. If I didn’t have any women friends who showed me there are nice ones in existence I would have cut myself off from ever being interested in anyone permanently. I’m still very careful because I prioritize 'rejection minimization' though.