Over the past few years, I have tried to set caring boundaries with my family, which has been viewed as an act of war. I feel as though I am at the end of my rope with my family and don’t know what else I can do, save cutting ties completely.
There are two issues here: the question of how to handle your family’s discomfort with your bridal-party decision, and the more general question of how to handle your discomfort with the role you’ve played in your family since childhood. Understanding the latter issue will help you manage the former.
It sounds like your sister has long felt hurt and rejected by you, and you’ve felt resentful of her. This is a common dynamic in families with a high-need sibling, whether those needs stem from mental-health issues or simply from a certain kind of temperament. The high-need sibling tends to take up a lot of emotional air in the house, sometimes so much that the parents, as you said, begin to feel overwhelmed and unequipped to help. In an attempt to keep the peace, they may accede to the high-need sibling’s requests and desires at the expense of everyone else’s. This might involve asking the other siblings in the house to “be flexible” and “help out”—by, say, including the high-need sibling when playing with friends, or caretaking in a variety of ways that aren’t appropriate responsibilities to place on a child or a teenager or even a young adult.
This is what happened to you, and you didn’t have much choice in the matter. The result is that you became angry and resentful toward your sister—even though none of this was really her fault. It was your parents who placed you in this role—not your sister—but because your sister seemed to be the problem, constantly interfering with everything from your autonomy to your joy, she became the focus of your rage. So it’s no wonder that she would crave your closeness and approval while you just wanted her to leave you alone.
The difference between then and now, though, is that you’re both adults, and with adulthood comes agency. You can either remain stuck in the past and react to your sister and parents from that place of childhood anger, or you can separate the past from the present by taking advantage of the choices available to you and managing your feelings in a more productive way.
For instance, consider the way you approached your sister about your wedding. So far, you’ve both reacted exactly as you did in childhood. Feeling perpetually rejected by you and possibly anticipating the perceived rejection to come, she preemptively rejected you: I’m not sure I’m going to your wedding. Instead of hearing the hurt underneath her comment, you went back to that childhood place of Here she goes again, creating drama. Then, rather than looking at how you contribute to the tension between you, you communicated your choice about the wedding in a way that sounded like a rejection, thus confirming her feelings of rejection.