What happens when a dumper isn't able to move on?

If a dumper ends a relationship and tries to move on by dating other people and exploring new options, what happens if deep down, he knows he still loves dumpee? If the new people he's talking to and dating wanted something more serious, would he be able to give that to them or would that be considered emotional cheating if he is still thinking about the ex?
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+1 y
so if my ex wanted me back... i would be a back up
What happens when a dumper isn't able to move on?
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