On breakups

So like 44hours ago, I broke up with my boyfriend.

It was mutual, and I actually had been thinking about breaking up with him. We had problems, and it seemed like he isn't great at dealing with problems or his own emotions. I realized we're not right for each other, as I was impatient with all his panic and insecurities through the hardest part of our relationship.

But still, after we talked it out and he left, when it hit me, that we've broken up, it felt like a truck has run over my heart and it hurts so much.

I don't understand, I thought I'd be more okay since we both knew for a while this wasn't going to last.

How is it that breakups still hurt so much even when you want it?

But I guess humans can't turn off their feelings like flipping a switch, right?