In my personal life, I do something similar. Outside of blood relatives, the "trusted" filter is "people with whom I am in an ongoing, loving relationship." Untrusted-positive is "friendly, but not loving or intimate". Untrusted-neutral is "acquaintances or friends of friends". In daily speech, I refer to the first (trustable, loving) category as "sweeties" and the second as "friends". The third are "people in the [name] community." Sweeties/trusted people are further broken down into "partners" (emotionally and physically-intimates) and "tocotoxes" or "partners-without-benefits" (loving, but not physical currently).
People in the trusted clump… since they love me, I assume they will have my back, and will take my needs and well-being into account when making their own decisions. I will trust them with my car, my bank account, or my children. And I will myself subvert my own needs when necessary, when they're in trouble or a crisis, to support them likewise.
Friends, to me… are a fickle, not loving, not trustable category. Too many people over the years have claimed to be my friend, even to be a close friend, and then done things to exploit vulnerabilities or harm or betray me. Not that partners haven't hurt or betrayed me also -- even as recently as last weekend -- but it seems to occur less frequently, and there is more incentive to try to forgive and heal things with a partner, given a greater emotional and otherwise investment. And most of my partners and I mutually, well, partner with each other, trying to avoid causing harm and respecting one another. These are not IMO characteristics of friendships, at least not as I see (or have experienced) them.
Still, these are precompiled groupings, needed due to my lack of talent in reading and assessing situational trustworthiness, and are subject to errors, misperceptions, and need to be revised to reflect actual behaviors over time. I may not be able to trust friends in general, but even for sweeties, their simply being physically intimate with me at times doesn't mean a sweetie will respect me or not betray me whenever it is convenient for them. It just seems to reduce, not eliminate, that possibility. There's no real safety. :-(
One approach would be to trust no one in relationship, I guess, but that seems dreary.
When a partner intentionally does or says something that pushes them into my not-trustable clump… it is hard on me. I wonder if my grasp on reality, or my safety, or my feelings of love and connection with that person are all called into question. And my trust-assessing skills, already shaky, feel invalidated.