I don't know how to cope

I have a friend with DID and I love him and love being his friend. But when it comes to his alter I don't know what to do.

She's a very sexual alter and is masochistic as well. She has tried to manipulate me into doing sexual acts but I always refuse or leave. Attempts to touch me in places have been made but I usually keep my distance, and my hands have been grabbed and attempted to be put on the body's chest area but when I notice I break away. I don't like a lot of what she does and now I just ignore her completely. There have been the couple of golden moments where I feel comfortable and like we can be friends/bond but those are only a few.

Normally my body has a fear response and I often feel ready for fight or flight since actions seem unpredictable to me.

Talking doesn't really seem to help much. From my interpretation it's made things worse for my friend, although he says that things with his alter would have gotten worse eventually.

I don't like being harmful and I do want to make amends, but I don't know. I don't want to do anything I don't like since I'm more about emotional relationships that never step into the boundaries of sexual things.

I really don't know what to do and need advice.

My SO and I have a rule that he only makes love to me.
One of my alters is very young and highly sexualized. She tries to seduce him all time. What he does is first, like you, he refuses. If that doesn't work he asks someone else to come forward and he'll call them out by name. (we don't want just anyone coming forward ) If that doesn't work he will leave.

It sounds like you are doing all the right things and being a very good friend. Good luck to you both.