When I recently pushed back against an assertion that academia counts as a cult, my main point was the importance of the axis "how does the organization respond if you want to leave", and I think I can draw a pretty strong analogy to relationships here.
Let’s consider a relationship between Alice and Bob, and posit that Alice is unhappy but finds it difficult to end the relationship. We'll look at several categories of what happens when she finally tries.
* Category 1: Alice doesn't want to leave because she feels like she'd be a bad person or she'd be letting Bob down, but in fact when she finally brings it up Bob respects her autonomy—he expresses feelings like sadness or disappointment, maybe asks whether her problems are solvable, but doesn't reinforce her feelings of shame. Bob could be a shitty partner in other ways, but he's not doing wrong on this particular axis.
* Category 2: When Alice brings up the idea of leaving, Bob reacts impulsively, begging or hectoring her to stay. This is bad and harmful, and it might happen the next time she tries to break up as well. But if a friend intervenes, Bob can agree that he shouldn't be doing what he's doing, it's just hard for him to help it; he needs psychological growth.
* Category 3: As Category 2, but where Bob's impulsive responses go beyond the pale, like threatening self-harm if Alice leaves. In this case, I would warn friends to never date Bob; it's just too much of a risk, even if Bob's reactions weren't coming from a place of malice.
* Category 4: Bob actively schemes with conscious premeditation to prevent Alice from leaving (or even from raising the topic). The abuser playbook: force Alice to sever connections with her family, to close off any external resources, gaslighting her that whenever she has a problem with Bob it's because she's being bad, etc.
For organizational examples, consider my opinions on Christian denominations: Category 1 is the Unitarian community; Category 2 is the average Ameri