I don’t see is B2 happening anytime soon, with the trifecta of weak ties to home, US SO and ESTA abuse.
For $190ish, you can try your luck, but probably best to just have the bf visit.
Others reading this thread should take note of the fact that 90 days means 90 days, and it is much smarter to avoid risking losing the ESTA forever by simple leaving a few days earlier.