Can my ex come after me for joint debt after I file bankruptcy?

my ex wife was awarded the house during the divorce. the negative equity in the house forced me to take on all the rest our our debt. with my support obligations, its too much. on top of that, our decree states that we are to hold each other harmless from the debts we agreed to take on. well, she never made one payment on the house after I made my last payment. the house went into foreclosure ruining my credit score and my second mortgage is threatening to come after me for the difference. (not to mention she got a couple cool grand as a parting gift in the cash for keys program) my bk lawyer says I'm fine to file bk on our joint debt with no repercussions from my ex because she failed to meet her obligations first. my ex is saying she is going to sue me for the joint debt after I file since she will prob be our creditors Target after I'm relieved. so who's right? I can see were my lawyer is coming from but my decree does say I'm supposed to hold her harmless from the joint debt I took on. anyone have any insight on this?