I have some personal history with the person I'm currently pissed at, so I need some objective perspective on this.

Background: this person and I used to be inseparable. Practically sisters. About two years ago, her mom died. One thing (among many much bigger things) that sucked about that was that my friend was stuck paying for two phone lines on her phone contract. I happened to be having trouble with my phone plan at the time, so we decided that I should take her mom's phone and pay half the contract. Since then, she and I have had a major falling out. It's a very long story, but it involved her getting into a relationship with someone and becoming kind of a terrible friend (hence, it's hard for me to be objective about things pertaining to her).

However, I'm still on the phone plan. I would have to pay significantly more for my own phone plan and it was just convenient to keep it going- I've just been sending her the payment once a month and other than that we don't really talk.

This last week, I got a message from Verizon saying that we'd used up 75% of our month's minutes two weeks into the month. This never happens, so I texted my former friend to ask if anything unusual was going on. She said not to worry about it, that she'd added her brother to our plan and needed to add more minutes, but that she wasn't planning on charging me for any potential overages. Personally, I think it's really weird that she not only didn't talk to me at all about this change before she did it, but that she had absolutely no intention of telling me and I only found out because she didn't get around to adding minutes before Verizon texted me. Yes, the plan is under her name, it's just so weird to me that she would think I wouldn't want to know there was another person on the plan (side note: that person is also a super sketchy semi-criminal).

Anyways, I texted her asking her a couple of questions, including asking what the total cost of the plan was now that she added a line. If it's cheaper per person, I don't think I should have to pay as much and basically be subsidizing the cost of her brother's phone line. She texted me back saying "your own phone line is its own expense so nothing has changed for you."


So my question is: Am I annoyed because I generally have quite a few (not so great) feelings towards this person, or is she actually being kind of sketchy? If I'm paying the same thing I was last month and have what she's saying is the same amount of minutes/data, do I have any right to be annoyed that she's also asking me to subsidize her brother's phone plan and not ask any questions about it? Should I just get my own phone plan, even if it would cost $25 more a month and I'm a poor grad student?

ETA: On the one hand, I asked her to make me an account manager so I could see the bills, and she did. On the other hand, it allowed me to find out that she added her brother to the plan in JULY, so it really looks like she was hoping she'd never have to tell me...