Hi bhopeful, I have the same issue with my W and mobile bill. I didn't make a point of it at first because she is worse of financially and was the one to move out. One month though it was 4 times as big and I brought it up but trying not to make a point, I asked if her phone had been stolen because, I'd received a large bill and was worried someone was running up a big bill before it got disconnected. The idea about changing the monthly minute plan as an approach is good, will let her know without putting her in a corner.
It's a tricky one, I've decided to keep on paying it for now, as I know the reason the bills are large is she is talking with family that are in another country. She's also making an effort to not run it up too much. If she pulls away more or if I find there is OM will pull the plug on it though.
When I'm stuck on stuff like this I try and remember that everything I do has to generate either good will or respect or better still, both. So if I feel she really appreciates me stumping up for the bill, that's good will. If I think she's just using me to pay it then there is neither good will nor respect and I'd pull the plug.
