The mind is a peaceful place when you know how to look at the same thing from different perspectives.

Sometimes we just need to see a problem from the latter's perspective too, to understand what they are going through and why are they doing it because many times what we see isn't really what they mean.

For example that one friend you had, who forbid you from making any other friends may not be exactly selfish or possessive maybe they were just insecure and scared. afraid that they might lose their friend to someone else?

I won't say we should always think rationally, because our feelings and the way how we handle it is something that makes us all different.