Talk to your pal. Tell them you've noticed they've been distant recently and ask if there's something wrong or if they're unhappy with you. If they are, try to work it out; if not, simply attempt to hang out with them more, call them more, and so on to see if you can rebuild the friendship. Sometimes we need people to understand us before we can understand ourselves. That's why the old adage "you never know what someone else is going through" holds true: we cannot always guess at the feelings of others. But because we care about them, we should try our best to find out! Distance may cause you pain, but only you can decide how far you will go to save a relationship. If you have been friends for a long time, then probably they feel the same way about you. So don't take it personally; instead, learn from it. The most important thing is that you be yourself around your friends. You shouldn't have to pretend to be someone else just to make them happy. And even though they may not say it, they probably want the same thing - for you to be happy. So keep doing what has made you friends in the first place: being honest and open with each other. In time, they will too.