"Being in a relationship with someone "normal" makes the "messy" one even more messed up in the long run."
Eeeh, what? Sorry, that sounds arrogant and kinda unresponsible to me.
I don't know in which way this character is messed up, but why should "normality" mess er up?
Because it confronts her with their differences? Is that always a bad thing?
She doesn't have to chance if she doesn't want to.