OP, you keep saying that when you talk about your own financial needs, you are "made to feel" like a gold-digger. I think you should break that down a bit. First of all, you don't have to feel the way someone else wants you to feel. When you say that you have been "made to feel" a certain way, what you really mean is that the other person is controlling the narrative within the relationship, either because of a dominant and stubborn personality or because of their material power over you.
You can speak up in opposition to this narrative, with your own, equally stubborn narrative. The thing is, when you lay out the truth in your mind, it shows up a flaw that is difficult to get past. The correct narrative here is that your partner has been using you as a low-cost nanny, bangmaid, housekeeper, for many years, without giving you the requisite respect or care.
And of course, if you refuse to give in to your partner's selfish and user-ish narrative about you being a gold-digger if you speak up for being treated FAIRLY, then it may push things to the point of him kicking you out, virtually penniless.
I see that there are many here on the thread complaining that you didn't "contribute 50%" so you were just leeching off of him. However, think about just the nanny aspect. Does a nanny get nothing but room and board? No. A nanny gets enough to rent, and even buy, her own home, her own food, her own clothing, her own vacations, AND still has enough left over to save for her future pension etc. And a nanny isn't also a housekeeper etcetera. You were BOTH of those things so you should have "earned" more than a nanny, and been compensated with enough to save for YOUR future.
But you weren't. Instead, your partner has treated you as if you are something to be used and thrown out when he's done with you, and as if you are a "gold digger" if you speak up to state your true worth as a person and as a partner. Your partner has completely been taking advantage of you financially.
You keep saying you don't want to leave because, in effect, you don't want the kids to be affected. The kids are already affected. Your son and daughter are both being taught that a mother deserves to be treated poorly. What sort of model is this for how they pick or treat a partner of their own? You are being treated worse than a dog or cat. Do you want your daughter to expect that future for herself, to pick a man who treats her as you have been treated?
And how are they going to feel if your partner passes away and they see you left homeless and penniless after all that loyalty to your partner? They will have to choose between giving up their own inheritance and seeing you in poverty. They'll pick themselves and feel horribly guilty. Or they'll pick you and feel resentful that they had to give up their inheritance for you.
I feel for you and I can't tell you what to do, because your partner has well and truly backed you into a corner from which it's difficult to escape. But your partner has shown he's willing to ensure the kids are taken care of. You need to take care of YOU.