Rainbow
I wish I could give you an answer on what you should do,
but I really don't know.
I like P7's idea of writing things out. Maybe you could write a list of reasons why you want to call her, and a list of why you don't.
Or you could write out your feelings that have been 'all over the place', and maybe it would help contain them. Sometimes when we write we gain new insights, or it just helps to get all the feelings out of our head and onto paper.

I think it would be OK if you called T......I don't think it would disappoint her. We all need a little extra encouragement sometimes.

I think it would be hard to have a friend who was friends with T. You said she is a new friend - how did you meet? Do you think it would be best to minimize your contact with her?

Let us know what you decide, if you want to, ok?