" People change. You change. Some relationships just aren’t meant to last beyond a certain point. It’s okay to simply let those friendships fade. This is a natural evolution of some relationships. Unlike romantic relationships, with friendships there’s rarely a reason to have a full-on breakup. Even if people go in different directions and the friendship slowly peters out, trust can endure. And unlike most exes, it is possible to rekindle/reactivate friendships later on when your lives are more aligned. "

― Reid Hoffman , The Startup of You: Adapt to the Future, Invest in Yourself, and Transform Your Career