Most Helpful Guy
I'd want her to be like "I'm breaking up with you but here, have this super hot replacement who's far superior to me in every way"2
Most Helpful Girl
I really don't want to get dumped by my s. o. but if he did, I'd probably prefer it either via text and/or video call. Text, only because he'd not be able to see or hear me breakdown crying. I wouldn't want to give him the satisfaction of seeing just much he has affected me. But at the same time video calling would be ideal because I'd want to see him as he actually says it then I could put the phone down quickly so he'd never see me breakdown and crumble into a mess. Plus, given how seriously I feel about him (I believe he is "the one"), I'd probably end up begging for him to give us another chance which isn't ever a pleasant sight.
Definitely not in person though because he'd see and hear me breakdown. Plus, when I feel upset, a hug from him is soothing and comforting so knowing he'd caused me to feel this way and I could no longer have him comfort me, I'd feel sick to my stomach.1