MIL vent!!!

soon2bMrsBerens

So this has been building for a while so I'll try to make a long story short.  Before MH and I starting dating he had a cell phone plan that his mom and sister joined.  She was paying it and then he would reimburse her for his portion.  When I get pregnant he added me to his plan as well.  Things were fine for a while until we got a call from verizon that the bill hadn't been paid in 3 months and they needed payment now which was roughly $400!! We had no idea she hadn't been paying so we had to scrape together the extra $300 to cover it.  We took over paying and did the easy option...auto payment so we never have to worry about forgetting!! So now we have to chase her month after month for their portion of the payment (BTW she stills pays his sisters portion who gets married Sept. 3, is 24, a nurse, and has her own place!!).  I've told her over and over that the payment comes out on the 7th of every month yet we just got July money from her yesterday!!!  To top it off...she went out today bought a band new droid and $30 data package...and added his dad to it who also bought a droid and data package!!! Never asked us if this was ok with us considering we front the money every month...and this will add an extra $80 bucks to the account! now she has the bright idea that she will take over paying it again!!! I don't wanna be the b*tch DIL but MH isn't saying a word!! What would you do?! P.S. MH and I just renewed our contract so it would cost a ton to get out of the contract and start out own account!