It won't be easy.

It'll take some effort.

But it's possible.

Go reopen communications with an old friend.

Figure out what they care about, hopefully it's sorta close to something you still care about.

And then dive into that thing giving it a real chance to make your own life better the way it made your friend's life better.

Then talk.

Catch up.

Use the new common interest as the medium through which you learn all about one another again.

You likely have a lot to catch up on.