You joined for the cause and stayed for the obligation
Somewhere along the line you joined something because you believed in it, and stayed considerably longer than the belief lasted because leaving would have let people down. Saturn in Sagittarius in the 11th house makes collective life a matter of conviction and then attaches a duty to it.
The 11th house is friendship at scale and the future built with others; Sagittarius signs up for what it believes in. Saturn makes the commitment binding. So your involvement in groups is serious, long, and occasionally continues well past the point at which you would honestly recommend it to anybody else.
The weight is the cause and the people separately
The thing you joined and the people you joined it with are two different attachments, and they came apart at some point without anybody announcing it. You have been maintaining both since. That is genuinely heavy, and most of the difficulty comes from treating them as one item when a decision about the first does not require a decision about the second.
The fear is having belonged to something wrong
Because your membership is a matter of belief rather than convenience, discovering that a group you gave years to was mistaken is a serious event for you rather than an ordinary reassessment. That prospect makes you slow to look. Looking is nevertheless the thing, and the discomfort is a poor guide to whether the examination is warranted.
It comes due when loyalty is asked for over judgment
The test is a moment where the group requires you to support something you consider wrong, on the grounds of solidarity. Your temperament will not do it and your obligations argue for it. Saying plainly that you dissent and are not leaving is the third option, and it is available considerably more often than it gets used.
A community that meets your own standards
What this builds, once you allow yourself to leave something that no longer holds, is a set of collective commitments you actually endorse rather than inherit from your own younger decisions. That is rarer among people your age than it should be, largely because most of them never examine the question at all.
Your friendships were formed around a shared conviction
The people you are closest to were mostly met through something you all believed in, and the belief did the introducing. Where your views have since diverged, the friendships have had to survive without their original foundation. The ones that did are the real thing, and it is worth telling those people so, because from their side it has not been obvious.
The future you work toward is a principle, not a picture
Asked what you are aiming at, you produce a state of affairs rather than a set of circumstances: how things should be, what would count as better. That is a rare kind of ambition and it never arrives, by construction. Holding one concrete personal outcome alongside it is what keeps the whole enterprise from being permanently unfinished.
The cause and the living keep converging
What you believe in has a habit of becoming what you are paid for, and the transition is where the money goes wrong, because you were giving it away first. Set a rate at the moment the thing acquires a budget, not later. Nobody who has been receiving your work free will suggest that you start charging.
You have funded things you believed in
A meaningful portion of your money has gone into causes, ventures and other people's projects on the basis of principle rather than return, and some of it will not come back. That is a legitimate use of resources and it deserves a stated annual limit, since without one the giving expands to fit whatever is available.
The group became your family for a period
At some stage the movement, the community or the circle around a shared cause supplied what your actual family did not: belonging, obligation, people who understood. That was real. It also means a rupture in the group carries a weight that seems disproportionate to anybody watching, and it is not disproportionate at all.