I am so sorry you suffered so much Friday night. I had this weird thought about how I was at the bonfire in my backyard Friday night while at the same time you were in M hell. I really feel bad for you.
It sounds like your H has not completely left the reservation. I'll never understand how someone can find someone else before knowing for sure whether they can fix their own M. I mean how can your H ask why you didn't fight for him then? If another W was in the picture why didn't he fight for you then? He's the one that had the OW, you didn't have another guy. I would think that would mean he would be aware of a problem first. Of course this is only logic and in no way figures into what a WAS will do.
You reacted as any horribly wounded creature would and you should not beat yourself up on top of already getting beaten up by your H's sitch. Sometimes, despite the DB game, pure unbridled truth and pain helps get to the heart of the issue. Maybe this outburst actually helped.