I think you're right. This LPT seems to lean towards the sentiment "I don't want a relationship with your friends, I want a relationship with you." But that doesn't exclude the motive "I don't want you to have a support system enabling you to leave me (my control)." Since the two aren't mutually exclusive.

It's always hard because you should want to trust in your partner, but that leaves a massive vulnerability to things like manipulation and other abuses if (they get you to) trust them enough to abandon your other support systems.

However, a partner not being willing to try talk therapy (where they do hold confidentiality to a higher degree) is a pretty straight-forward sign about what their real concern is between the two.