His children and I go without for his parents….

“My in-laws can get anything they want from their son while his children and I have to go without. This is getting in the way of our marriage and he can’t see it. Quite soon I am going to leave him if it doesn’t change. This is not something we can talk about because of our culture.”

You get to decide if you wish to be subjected to cultural expectations at the expense of your marriage and your mental health. I’d suggest you have a conversation, and not a confrontation, with your husband over this matter. Do not suggest he resist assisting his parents, but rather finds a way, with you, to serve his parents without sacrificing the needs of his immediate family.

Dialogue first. Negotiations, second. Ultimatums, polarized positions (“us or them”) to be avoided at all cost.