I don't even think Monica is that bad as far as FE characters with obsessive crushes go! There's a difference between counting the exact number of times she has tea with Edie and, say, watching her sleep while counting the exact number of times she turns over. (That's not meant to be a potshot against Tharja, by the way; she's just the first example of another obsessive character that came to mind.) Plus, Monica's perfect memory means it makes sense that she's able to keep track of things.

People twisting characters into hating whoever they themselves hate feels like childish playground bullshit to me. "I don't like you, so I'll make my friends not like you either", or something like that. e.e