What happens when your partner doesn't see the value in you and continuously hurts you by searching for something in others knowing it hurts you?

There is another scenario:

I would ask myself why I consider it worth my time to be with someone who does not find me valuable. Identifying this answer will over time protect me from finding myself in this same predicament over and over.

I believe this non-love is the best I can do and spend all my time and energy attempting to preserve the very thing that causes me pain.

Ive been pretending to be okay and acting as normal as possible, but Im actually completely heartbroken after a recent breakup. Its painful and really affecting me, to the point where I cant concentrate at work, Ive lost my appetite, I cant sleep, and It feels as if my whole world has been turned upside down. I loved him so much. He said so many cruel things to me and it made me realize he must not have loved me the way I loved him, or he wouldnt have said such horrible things. How do I handle the heartbreak and why cant I accept that he didnt love me and just forget about him?

In one scenario, I stay with this partner, wonder why he doesn’t love me, and begin living in a world of my creation where I believe that, unfortunately, I am not worth loving.

What happens?

I would leave this partner to grant him full freedom to go find whatever he is looking for and spend the time and energy that I put into that relationship getting to know myself. What I would find is someone flawed and worthy of love.

Why did I move on so fast from a relationship that was my whole life and I was so attached, I moved on by 2 months?

“Making someone love me” is the most painful, most fruitless of efforts, because love cannot be manufactured in this way.

I would work hard at only being interested in people who are equally interested in me.

If my “partner” didn’t see value in me and hurt me searching for something in others, I would remind myself that I cannot change people, “make them see” or “make them love me”.

What are some life hacks for living on your own?

I would realize that it’s not my partner who is hurting me. I am hurting myself, by agreeing to stay with someone who is looking for something he is not finding in me.