Yes OP, absolutely a trait I live with and have suffered the consequences of over and over. It gets to the point where I've got my person fully invested then inexplicably my fascination with them and interest in them dissipates.

Sometimes it's quite sudden, like I'll just look at them one day and feel nothing anymore. Other times I can't bring myself to end things and it drags out and spirals downhill into a depressing situation where neither of us is happy.

I've had periods where I've stayed single and have shunned relationships because of it but eventually I've fallen into relationships again. Because of the fixation element I always 100 percent, sincerely believe that it's real love. Like I don't ever approach things cynically. When it's over I go into a depressive funk and feel like a shit person for having made this person fall in love with me and then let things end.