This has happened to me more than once.
I have a friend Sally who has annoyed me for certain reasons. One day, Sally tells me that it seems like Jane has been annoyed with her but she does not know why. When she explains what has been going on, it seems to me like Jane could be annoyed by the exact same things that I find annoying/off-putting about Sally. I don't know Jane, so I can't say for sure.
How do I tell Sally that perhaps those things which annoy me (I've never told her that they annoy me) are what's annoying Jane? Would I only mention them in the context of the situation with Jane, or do I also mention my personal experiences/grievances with Sally?
If it matters, in one instance Sally was extremely confused about what would cause Jane to distance herself from Sally. She brainstormed a list of possible reasons but came up with counterarguments for each one to make them sound farfetched. One or more of the items in her list are indeed things that bother me about Sally.
For example, a reason Sally came up with: Perhaps Jane thinks I am trying to mooch off of her.
Sally's counter-argument: But I offered to pay.
My view: Sally is one the biggest moochers I know.
Both from my experience and from the story she told me about Jane, the rare times that Sally does offer to pay are inappropriate. For example, she may offer $5 for a half mile ride to her house. While tempting to accept because she rarely offers up anything on her side, I would not feel right accepting money for such a short ride.
How could I tactfully react?