I'm pretty sure this is how all well-thought out relationships should go. She...or he...has expectations about the relationship or marriage. So it's tracked and if it doesn't look like the work completed is keeping up with the total work after a few iterations, if the velocity is flagging, then perhaps it's time to call it a day. If you were really careful, you could even watch for negotiated client-added work to see where expectations were changing, scope had increased, or acceptance criteria had been redefined. If you think it will offend your significant other, than do it for a friend's relationship. I'm sure they'll appreciate seeing their relationship captured in burn up. "What? You used a burn up and not a burn down?!"
Snarky: I told her my work completed line was never going to meet her project scope line.
Title: So you broke up with her using a burn up chart?