The friend I'm talking about is a really good friend and person in general. He just goes through random moments where he acts in a very selfish/greedy manner, while he can be generous other times. It's just kind of frustrating sometimes, but I realize no one is perfect and we all have our moments. I was mostly wondering if I'm being a good friend for letting my friends know when they act irrationally or should I just let it slide? I feel like with some people, it can create a feeling of resentment towards me in the longterm if I'm always the one calling them out.