Why is this so crazy!?

So I had to remove myself from a cl at the gym.. the instructor(who is a woman) and her friends would constantly stare at me (another woman).. this was going on for almost a year . she would also call me babe and focus/stare at me in cl.. her and i would play staring games while she was instructing the previous cl or in the cl i was taking. one day i was leaving cl and she was talking to another woman whom she hugged and then looked at me after she hugged her.. i would be on my cell texting someone laughing and smiling.. I would then receive a call from her friend a mutual friend (a old kickboxing teacher asking if i was seeing someone). i finally removed myself from the cl.. she denied everything and stated that she was christian. a good friend to her has been talking to me and wanting go out hangout with me ( but this person never talked to me before).. while hanging out with this friend, of the instructor, all this person would do is talk the teacher up (like how funny she is and wouldn't stop talking about her. she asked me who i talked to outside of the class and hung out with. she also asked if i was dating anyone) and keeps asking me if i was going to class (it has been a couple of months since i have left the class).. i have known the friend of the teacher since last dec but never once did she speak to me.. all of a sudden now she talks to me (only on the weekend to go out).. this woman is 38 yrs old and the instructor is 40. so why would her friend be so friendly to me all of a sudden? The friends of the instructor always mention her name to me (but why?), keep trying to get me to go back to her class, and want to hang out with me on the weekend (for someone who never has talking to me before).