Ok this happened to me in 2003, was married for 21 years, ex sought out a different lifestyle IE sleep with other people. Live in Cali makes no difference. Here's the scoop and I assume NJ is a community property state. She gets half of all assets regardless, no arguing no changing. Child custody is based on interviews with the children if of age and of age is determined by the family court when talking to the kids no strict age in Cali. Once thats decided everything is based on a formula they plug your numbers her numbers and cusotdy figures and out comes a number that's what you pay. Any marraige over 10 years is considered eligible for lifetime alimony. under 10 alimony for one half the length of the marriage.
My specifics, self employed ex wife an ER nurse but only worked 3 days a pay period, kids were 13 and 17 at the time. Niether child wanted to live with Mom as she stated she wanted to move to BF Arizona and be a "hippy"(yes thats a quote). Ok my initial settlement was alimony of 4100 per month, ouch. We dug in and proved she should have to work normal hours as in 3 days a week so that effectively cut her alimpny in half, actually 2275 a month. No child support form me, she paid $150 a month to me.
Now the difference for me was I/am self emlpoyed and incorporated and she wanted no part of the business when I started it 10 years before the divorce, actually have that in writing from the incorporation. Since I could not afford to keep the company running like that financially I had to let all my employees go (only 4 people) but that also meant less projects that I could do, we drafted that up and appealed that and they cut it again to $1300. OK that I could deal with I guess. Well lo and behold when the time came for the divorce to be final she went and got remarried because as she stated she could not live on the $1300 and did not want to work 3 days a week needed additional income form some source. So I basically only paid her 7 alimony payments.
Long and short of it is the only way I know and I obsessed researching this crap back then was to prove she had the abaility to earn more money especially with the fact that the kids lived with me and as you see they reduced mine legally thru the courts from 4100 to 1300 based on her needing to work a "normal full work schedule" and me needing to cut back on work and travel since I had the kids. Taking a lower paying job, quitting etc will not work and only get you on the courts radar for collection, I strongly suggest you find a good family law attorney, one that is reccommended by father rights groups in your area and go that approach. You will have to pay but possibly not as much but the length is up to her. Hopefully she is as stupid as my ex was and only sees the short term. Oh and it was hilarious in one of our preceedings when my ex told the presiding judge/family law commissioner she wanted to live a "free sprited carefree hippy lifestyle" and the only reason she wanted to leave was she met someone who she was more physically attracted to. The judge/comissioner was a women and she just shook her head looked at me and said sorry to hear that. Also she had an absolute idiot for an attorney and a friend who is in criminal law knew him and referred me to someone in family law who hated the guy and loved sticking it to him. Good luck buddy, it sucks but can be managed and lessened with diligence and fortitude. Oh share nothing with her or your child about legal proceeding the attorneys can hash that out.