It sounds like she is trying to talk to you like a friend, but in a really delusional and insensitive way that is very inappropriate. This is not acceptable, but you can't show her it hurts you so you have to remain polite and not allow it to escalate into an argument. When she hurts you say something like "you know, I don't even know what to say". If she fights with you, validate, remain calm and detached. I know easier said then done.
BTW, I only thought you should assist her in the case of a health issue or medical emergency. I don't necessarily think being a nice guy will help.
As long as you are physically separated what type of boundaries do you feel you need to set? Just doing nothing right now other then things for yourself is your best bet. And however tempting and consuming it might be, do not ask about OM and do not pursue. This will get easier as time goes on, and the thoughts of what she is doing will diminish.m
Me: 42 H: 43 Twins age 5 Physically Separated 7/2015