Let me preface this by saying, I am in Mexico and laws are different so obviously I don't expect more than general advice.

About two months ago, BM asked DH for more money for CS.  DH pretty much blew her off (stupid move, but whatever) and figured he would talk to her about it when we went to see SS.  We live out of state and only see him one weekend a month.  About two weeks later, we drop-off SS and DH tries to talk to BM about CS.  She says she doesn't need it anymore and to me obvisouly this means she is pissed that he blew her off and went to see a lawyer.  Sure enough, I look up their old case number and it says a petition has been filed (not sure if you can check this online it the states, but in MX you can).  A few days later, they take the paperwork to our old lawyer to try to serve him since we no longer live in the same state and she doesn't have our address or anything.  Our lawyer tells the server that he no longer represents DH and cannot receive the papers on his behalf.  Lawyer manages to get in touch with DH and tells him what happened and that the paperwork basically says BM is suing for an INSANE AMOUNT of backpay plus an increase in CS.  Apparently CS in MX can be increased based on inflation and the CS she is requesting is almost double what he currently pays.  Let me note that DH's wage has not increased in equal proportion.  Lawyer says that as long as DH can prove that he isn't making double what he was making when CS was first established, it's very unlikely she will get any back pay especially since their original agreement doesn't say anything about how/when CS should be increased.  Lawyer also says that based on DH's salary, it is very unlikely that the increase in CS will be approved.  How is it possible that CS will not be increased SEVEN years later, you ask?  Because DH agreed to a ridiculously high amount of CS the first time around just to get it over with.  He also buys SS clothes, shoes, etc. all the time and gives money to BM whenever she says she can't afford something (doctor's visits, school supplies, etc). DH has no way of proving that he has given her money in addition to CS for the last seven years because he never kept nor asked for receipts for a damn thing.

Now to my dilema.  BM called DH and told him she is suing him and needed our address.  DH said he needed to talk to his lawyer and he'd get back to her.  Lawyer basically said not to give BM our address, that her lawyer has to perform some kind of investigation.  He told DH this is very expensive, which is probably why she straight up told him she wants his address.  I have NO idea how much her lawyer is charging her, but she is forever complaining that she doesn't have money so I don't know where she is getting the money to pay for all of this.  It is very possible that she will run out of money and try to settle with DH.  DH is beyond pissed about the backpay and the fact that she filed papers without trying to talk to him first (although I pointed out that she DID try to talk to him and he blew her off for two weeks) and says he is going to follow the lawyer's advice.  He says she is just pissed because he didn't get back to her fast enough and did this out of spite.  This may be true, but to me, not giving her our address is just as petty as what she is doing, and is probably going to cause a lot more problems.  We went to another lawyer to get a second opinion and he basically told us to follow the same course.  I just don't feel right about this...any advice?