Should I tolerate this person?

I have a friend (I call him AB), actually I do not know if he should be called a friend, that often gives me the impression that he is deceiving me. Once while walking with AB and another friend, we stopped to buy some beer. The other friend bought himself beer and also lent AB money. I decided to buy a beer too, but I was $1 short, I asked AB if he could lend me $ 1, but he said that he did not have $ 1. We kept walking and then we stopped again and AB bought himself a beer and also lent the other friend money. I thought about saying: “But you said you had no money!?” but I did not say that. Maybe the explanation to this was that he had a $10-bill but not $1. What is really weird is that I had lent him money many times before. And that was one of the few times when I asked him to lend me money.