If another chick slaps a girl on the ass, is that indicative of homosexuality?

[I love the color red]

I use to hang out with girls who would smack me on the ass all the time, and tell me that I looked good. LMAO. I swear I thought it was just fun and games, come to find out these same girls are like undercover homos. Like they're just coming out of the closet one by one, I feel soo silly because I didn't know they were really gay. All of the signs were right in my face all along, and I just didn't get it. I never thought anything of it because we all had guys that we were dating or talking to. I no longer hang out with these people because I'm convinced they only hung out with me because they were attracted to me, and wanted to turn me out.
So what are some more signs that someone is gay??