Is it fate or just him having me as a backup?

no matter what I try my ex keeps coming back into my life I want him in my life but as a friend every time we talk he asks the same question if I wasn't in a relationship would I go back to him he cheated on me 5 years ago but we were only 17 and 18 and he just got divorced but not because he cheated on her she fell out of love with him and everytime we talk his feelings for me grow and I get confused I love my current boyfriend more than anything but yet my heart still flutters whenever he makes me laugh or smile

Is it fate or just him having me as a backup?
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