My mother is terribly hurt that I feel no attachment to my five step-siblings and no desire to spend even one holiday every couple of years with them.
They are all sorts of crazy; two daughters are in and out of rehab and mental institutions, and the third ought to be. One son has recently spent time in prison, for what, I don't know.
Every moment I was forced to spend with them as a kid was torture, and I have no desire to expose my two children to their generally immature, sometimes ridiculous behavior. My sister goes every couple of years to keep the peace, and strongly believes I should, too. My husband refuses to go no matter what I decide ... he can't abide them even for an afternoon. I got the full-court press from my mom this year. Am I under any obligation to spend an occasional Thanksgiving with my mother, her husband, and his family?
Answer: Mom is "terribly hurt" because you avoid the children of the man she married? Disappointed, OK, but if you're representing her accurately, then she (1) regards your opinion of your step-sibs as a reflection on her; (2) expects you to fix that for her; and (3) is thinking of herself, not you, as she applies her annual arm-twisting.
Three strikes against the likelihood that Mom herself is in great emotional health.
That's all built on an "if." However, even the basics - step-sibs are unusually troubled, Mom won't take "no" for an answer - suggest you'll have no Thanksgiving peace until you resolve whether you owe your mom a visit, or she owes you a break.
To get to that point, you also need to figure out what you owe yourself. (And yes, you owe it to your husband and kids to spare them.)
Before you start sorting, though, there's something you owe everyone here: compassion. If only one stepsister had been in and out of mental institutions, I doubt you'd say out loud, even anonymously, that you want no part of her "crazy."
Yet at least three, possibly four, step-sibs are dealing with significant mental illness. One frailty generally inspires sympathy, but a barrage of them tends to pry loose our contempt. And while I agree with not exposing your children to family members who apparently aren't managing their illnesses effectively, I'm reaching for a non-scolding way to suggest you soften your approach - even if you ultimately decide not to break turkey with this family next year.
Showing compassion for yourself counts, too, particularly for the youthful version of you. Obviously your mother's remarriage put a painful dent in your childhood.
If you believe your mom knew the chaos she was bringing to your life, and prioritized her own needs or wishes over your emotional (even physical) security, then that's a legitimate grievance. You also have a fair grievance if she had no way of predicting the chaos, but still failed to shield you from it once it had clearly set in.
This is a growing stack of "ifs," but, last one: If true, these are grievances against your mom, not your step-sibs. And, again, what you owe your mom, or don't, is the key to a satisfying decision when this annual bird comes to roost.