Did you ever experience a break-up of a relationship? Why did it happen?

I am not wanting or needing to break up with anyone. This is not an advice-seeking question.

But I was having a discussion with my girlfriend about some of my relationships when I was a teenager—and how they eventually ended or drifted apart. And it occurred to me, that these were, in their day, really traumatic events. I realize that many adults go through painful break-ups as well, Some are scarred for life.

What attracts a person to someone in the first place whom they think will be their soul-mate possibly for life, if it is not meant to be, or the relationship dies? Are there ever amicable break-ups where both parties agree and there is minimal hurt? Why do relationships not work out?

These are fairly major life events and turning points, but because they are personal and often involve rejection and hurt, and sometimes betrayal, we seldom talk about them.

If you care to discuss, tell about a break-up you had in the past and why did it happen?