I think you are right. I have come across this terminology (s'en deprendre) in books about addiction. I just flipped through three books, and couldn't find a sentence with it. But I think I would translate it like this:

"Le materiel apporte en psychotherappie fait l'objet de reprises. Pris et repris, parfois pour mieux **s'en deprendre.** Avoir prise, lacher prise..."

"The topics brought up in therapy are often revisited. Visited, and revisited - sometimes to further let go of it [or "to further liberate oneself from it"]. "

As to the next sentence, I'm not sure I have a good translation. Maybe "Hold on, let go" or "Contract, release" or "Constrict, release". I realize that "lâcher prise" is a passive phrase, so it would be like "let yourself be taken". That's the sense it has in meditation, to let oneself be taken over by God/the universe/nothingness - whatever. You probably already knew this part anyway.

Hope this helps. If not, sorry. I'm open to clarification of my thinking (contextual pun). Best of luck with your work.

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