[martiandog]

I've been best friends with "mary" for over 20 years. The last few years mary and i have been growing apart a bit and she and my mom have become closer and closer, and hang out all the time without me. sometimes they invite me but they always make plans together first. i've told my mom it bothers me and she said she would stop but she still does it, she just makes excuses every time or tells me how lonely she is. sometimes she will ask "permission" to call mary or make plans with her. I don't know what to say, i can't prevent 2 adults from being friends but it feels disloyal and hurtful from both of them. why is this happening and what do I do?

Since you are a friend with "Mary", I assume she is in your age. At this case, it makes sense to include you in all their plans, unless you are no longer a friend with "Mary". At that case, I am not sure.