My (24F) younger brother (21M) has become very misogynistic and racist following his breakup. He was dating this walking-red-flag girl (22? F) for about a year and a half. She rubbed off pretty much everyone the wrong way, but it was his first relationship and he was happy to be with someone "out of his league."

Apparently what happened was she told him she was waiting to have sex until marriage while in reality she was treating him as a backup and hooking up with other guys. I don't know what was going on in her head, but that's the general idea from what I got. Eventually, he found out and obviously was really upset, confronted her, and her response was to break up with him and make fun of him. I didn't know until recently, but apparently she told a bunch of their friends that she wouldn't have sex with him because he has a microp*nis. I don't think that's entirely true, but it struck a chord with him and became a bit of an obsession for him apparently.

Fast forward a few months, he has become a shut-in and is using a lot of "redpill" lingo about women and minorities. Frankly, in the beginning I found it somewhat entertaining to refute the made-up stuff he would repeat from anonymous accounts on Twitter, but it became more and more deranged. It all blew up last week when we were home amd he found out I had been on a couple of dates with a black guy. He started screaming stuff I will not repeat and then went into his room and was audibly crying. That's what prompted me to ask more some friends who are still in school about what is going on with him.

Our mom has been a little worried about it but doesn't know all the details (I think) and she is probably more glad he at least broke up with that girl. I think he needs a combination of compassion and getting slapped back to reality. How do I proceed?