Sometimes my bf can be a little harsh..

My boyfriend is the most caring person I've ever known - seriously, he's amazing when it comes to looking out for me and protecting me, always treats me right etc. But sometimes, i think it's when he's tired I'm not sure, his tone changes a little and he's more blunt in his responses than usual and it comes across as slightly harsh. It just kind of gets me down because I would talk to him about it, but he hates the idea of hurting me intentionally and unintentionally. So he'd get upset if i tried to tell him it was making me upset. Like i said i know it's probably because he's tired or stressed maybe, but ladies do you have any advice??