How do I cope with the fact my next girlfriend would not be as beautiful as my ex?

I broke up with my very pretty ex because I was not fulfilled in the relationship anymore. Now I am going out with some girls and most of them are not as attractive as my ex, but one who is even more attractive, but already taken. I try not to be shallow and I focus on their personality, but I am clearly not as physically attracted to them as I was to my ex.

How do I cope with the fact my next girlfriend would not be as beautiful as my ex?
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