I actually had my first FemShep romance Jacob in ME2 then let him die in the Suicide Mission... specifically because she romanced Liara in ME1 which I really did wanna continue
"Hi, I'm
Kestrel. I didn't want to continue my relationship so I let my lover die. Breaking up makes me feel uncomfortable. I'd rather avoid the personal embarrassment and let my lover die a horrible death on an alien spaceship."
You are the worst person in the world.
Seriously, next time you want to dump somebody: Send a text message.