What is she playing at?

Can someone please help me. I'm struggling to understand what she wants from me.

So I'm gay and I have a straight best friend who is married with kids. One minute she will be completely flirting by putting stuff down my top or saying she misses me. Slapping my arse. The seductive looks she gives me. She hates it when I stay at another friends house. She gets jealous when I go out with friends. When she sees me she is all smiles

Then in the next breath she is cold as a cucumber. She is messaging like a friend would. She has taken a day off work so we can spend the day for me.

Her husband accused us of having an affair with each other. I wanted to cut contact with her as mentally I couldn't cope with it she was adoment she didn't want me to.

I'm really confused by all this. Amy advice would be great
What is she playing at?
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