Back in the day when my tolerance was so low I could trip balls, the same thing happened to me about half the time when I got really high. It never really caused a problem with friends though, probably because I'm accustomed to be introverted and feel 100% comfortable not socializing. And I think that's what you need to do if you're so high you can't socialize, just throw on some headphones and listen to music, stay out of the way, let the party go on without you. If anybody asks what's up, just say "man, I'm too high right now, I'm just gonna ride it out".

A real friend shouldn't be mad at you or want to ditch you just for that, so long as you're not doing it on a regular basis. From now on just know how to say "no", and stop after you've had enough for a light buzz and enjoy that. I find the mild highs have qualities of their own that make them just as, if not more, enjoyable.

And as UnknownFigure said, you need to ask him what's up if this continues. He's your friend, you should be able to talk to him. If not, he's an asshole and you can find better people.