This is just my take on it and is based on my friend who I will call E.
DP and I met E when she started going out with a mutal friend of ours. She is very pretty and "full of fun and up for a laugh". But she used to get unwanted attention and male friends (even married ones) hitting on her and trying it on an she could never work out why.
I used to observe her when we were all in a group. She was loud, always laughing, but always spoke about sex, talking about blow jobs and make crude jokes with her DP. He would make crude jokes about her and she would join in. This probably made her look sex mad and up for it.
Of course nothing was further from the truth. She was devoted to her DP and was not interested in anyone else. She was always suprised when men hit on her or started to send her inappropriate texts.
E is still a good friend of mine and she has a heart of gold, but the way she acts seems to send signals that she is not aware of, signals that spell out she is sex mad and has no limits, so is mystified when something happens.
Maybe OP you should look at what signals you are sending out. I am not suggesting that you are as loud as E but she never realised the signals she was giving out and to her it was just having a laugh not realising that men and women read things differently.
My DP had a crush on E for a while, it was a rough time for us. 