How to keep busy friends?

I have a few friends who are always so busy that I don't often hear from them, but when I do, we talk for hours and it's like we talked yesterday.

I think the best thing we can do is not get upset if we don't hear from them, because it's not intentional. I used to be the type who would not contact a friend if I had not heard from them in a while because I thought if they wanted to talk to me they would. I have learned that this is a silly way to handle things, and I lose friends that way.

If I have a friend who I know may not have the time to keep in touch as often as I'd like, I will make the effort to keep in touch to let them know I'm still here and always thinking about them and available whenever they have some time or whenever they need me.

I also have to remember that just because we don't talk ever day, doesn't mean we're not friends.