I have known this friend for 16 years. I moved away about 14 years ago. Every year he would call me on my birthday. This worked out really well because we would discuss everything from that year. We really don't have anything in common so calling more than that would lead to awkward silence. Four years ago he suggested we get together and have lunch, I agreed not knowing that this would lead to hundreds of phone calls (often more than once a day), and him making plans without telling me about them first. Normally, I could deal with this but he gives me a guilt trip if I don't call him back right away and gets angy when I not free on the days he schedules things. It would be easy for me to end this kind of a friendship if he weren't such an old friend. On top of that he really doesn't have social skills and doesn't have any friends of his own.
HELP ME PLEASE!

Calling you every year on your birthday? Sounds like he cares about you. But, so many phone calls more than once a day sounds like he needs a life of his own. You can't keep babysitting this guy.

It sounds like you have not been upfront with him about how you feel and think. Have you tried doing that? Being upfront with him would not necessarily be letting him down. Not being honest and upfront with him would be letting him down.

It might help to talk to him in a way that is neither aggressive or intimidating.

If you have not been upfront with him, I would do the following:

I would say the following to your friend: Hi, (name)! I have a problem that I think that you could help me with. Would you be willing to help? He, of course answers "Yes." Well, I am having a problem with you calling me so much and making plans (for us?) without telling me first. I appreciate your friendship, and I want it to continue with that friendship. I have loved being your friend over the years. (Give examples of the things that you have enjoyed about your friendship.) But I've got things that I have to take care of in my life. Don't you too? Can you help me with this problem I have? Maybe we could work together on it?

Puts the ball in his court. Makes him feel good that he could be a part of the solution to "your" problem.

As things progress, make suggestions to him about things in which he might like to get involved so that he has more of a life of his own that has some variety to it. I.e. clubs, organizations, etc. that have to do with the things that he is interested in. For me, that would be music, gardening, archaeology, coin collecting, playing chess, a club to discuss books that I and other people have read, a hiking club, bicycle riding, a club involved with activities that celebrate my Celtic origins.

If this does not work, suggest to him that he get some counseling. And, as a friend, it would be okay to say that.

"The best mirror is a friend's eye." Knowing this helps us to see and realize how we really are.

I hope and pray that the foregoing has been helpful to you!