I feel so confused and hurt!?

I have a guy friend that has suggested a friends with benefits relationship. Lately, we have become extremely close and have started telling each other I love you. I have been happy with this because I had deeper feelings for him than friendship and wasn't comfortable with fwb. The problem is that we were hanging out at his house the other night with some friends and he totally ignored me. I don't get it. My sister was the only other girl that was there and I know he is not attracted to her. The last time I talked to him before that night was Sunday and we were perfectly fine when he left the movies. Could he be mad about me not wanting to be fwb? Any advice would be greatly appreciated!