Am I evil for no longer finding my girlfriend attractive?

We split up for months, and in the meantime, I got in better shape. And met a lot of attractive women and slept with them. And now I don’t think my girlfriend is as attractive as I once thought. She’s showing her age (she’s in her 40s, and I’m in my mid 20s). I feel bad, but I still have feelings for her. And she was the one to take me back after months of no contact.

Am I evil for no longer finding my girlfriend attractive?
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