Have you ever had a relationship that was mostly one-sided?

I once read a saying I really liked – might’ve been on Fluther – that said that relationships are rarely 50/50, they’re usually more like 70/30, but what should be about 50/50 is the time spent being the 30.

I know I’ve had a relationship where I was the 30 or the 20, or maybe 10 a lot more than 50% of the time. Have you? Or, conversely, have you had a relationship where you were 70 most of the time?