When A Guy Goes Limp?

Ok…I have never done anything like, so obviously I really want some advice. I met this guy a few months ago while he was in town visiting a friend…he lives far away from me. Anyways, we went out while he was here and things were great! The next night, his last night, he went out with friends and came over…a little drunk. We were fooling around, but he couldn’t get it up. I never thought too much about it. After he left we talked every day for at least an hour for 5 weeks. Then he came back out to visit me for a weekend. Again, we were fooling around, he put a condom on and it went limp again. Anyways, I sort of freaked, because I thought it must be me! I asked him, but he said it was definitely not me. It was a little awkward, but after a little bit we got ready and went out and had a good time. He left the next day, and everything was fine. He let me know he made it home ok, but now I haven’t really heard from him. My guy friend says that the whole limp thing is really hard for a young guy to take….especially when it happens with a girl he really likes….especially twice. It doesn’t bother me that much, as long as he can reassure me that he finds me attractive and is still into me. So, my question is for the guys….in your opinion, why haven’t I heard from him?