Have you tried to improve yourself for someone? How did that work out?

I was desperate to keep my boyfriend interested so I tried to improve myself to keep him. If he thought I was putting on weight I altered my diet.
When I was too skinny I stopped swimming as often.
It fucked with my head, my body and my self esteem...
He wasn't a good man. He played with me because he knew just how much I loved him.
Have you tried to improve yourself for someone? How did that work out?
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