Ask her. If you don't want to do that I guess you can be the bigger person & keep inviting her. She'll see through but if she doesn't then I'd probably stop, but yeah, that's me. Good luck. :}

She may feel threaten by you and that is why she doesn't want to share the lime light with you. I would not continue to invite her, she is being a leech.

I would ask her why she doesn't invite you. then go from there.

Ok dear have you marked how is her behaviour with you on different stage. Means when you are off hospital do you have time to be together and yes than how does she behaves with you ? If its same way than she seems to be selfish to just think about herself and dont care for even them who actually cares for her. Sorry to say but she being not nice at heart, may turn out to be a doctors who just work for the sake of money. You than need not be so kind to her because you are wasting your kindness towards somebody who dont reverse it and dont deserves it.

Take your friend out to coffee or a drink and talk to her about this. Be kind and gentle and keep in mind that she may not realize she's being rude. Do not have this talk at home, if things were to get heated your home would all of a sudden become a battle ground. In open public, people are more likely to be civil and not make scene. Better to go to a place you've never been to and never plan to go to again so whatever happens( fresh slate or disaster) stays there. However I'm not done with you yet,lol. Your friend may be looking at you as a competitor, inviting you along may make her feel like she's giving you leg up to beat her and and giving her an edge when you invite her to your cases.