I tend to cycle through a group of friends frequently. The longest I've gone with hanging out with the same group of people is 2 years! And that is with almot always having multiple groups of friends at the same time.

Barring that, I've had individual friendships that have lasted for years.

I find it worth it, even though I put so much effort in only to be let down. Just because of that rare chance that I DON'T get let down.

I have, however, learned to not bend over backwards for people. If it is going to cause me much inconvenience then I'll refrain - if it's not going to cost me anymore than a bit of my time then I go ahead because I get satisfaction from helping the world even if I get nothing back (friendship is getting something back... I try to not expect that from people anymore). I don't really expect to get much back from people, and I find that if someone isn't putting much effort in to a friendship... well... I'll drag it on for a while to make sure that they're not just in a rough patch (unless I know how they're with their other friends) then eventually I'll just stoop putting in the effort.

It's tough... but I'm a whoooole lot happier and a whole lot less drained!