Yes, new partner is not a spouse. It all depends on the terms of your divorce agreement on both child and spousal support.
If she remarried the spouse in most cases it would end, but in some it doesn't even after remarriage for spousal support.
The new spouse or partner is in no way responsible for your children, that continues until the children are at least 18 years old (some go to 21 if they live at home and go to school full time).
I have 2 kids from my first marriage and I'm remarried. My ex and I are the only ones responsible for the 2 kids we have together, not my husband or any spouse or gf of my ex, regardless of what any of them make. My husband provides well for those 2 kids (along with the kids we have together) because he chooses to, not that he has to, he considers them his kids too. My husband is a Cardiologist and makes a base salary of $450,000, my ex is a state trooper and makes a little over $100,000, my ex making less doesn't exempt him from paying child support and providing for his kids. My ex and I make around the same (I also work) and the child support is based on our salaries not my husband's. You'd be correct in assuming that I don't need the child support but that hasn't' always been the case and there's always the possibility of something happening where I would so I continue to receive it, I save it for the kids the child support I receive for them goes into bank accounts for them.