As someone who works in treatment, I have seen this kind of scenario play out many times. Most of my experience has been separating children from abusive parents. This is typical for victims of abuse--separation from the abuser. It would be unthinkable, unethical, and possibly criminal for a mental healthcare professional to recommend that a victim stay in the abusive relationship. Right?
I have worked in a number of treatment facilities over the past decade or so. I can't say any of them handle religion in a manner which doesn't cause problems. Utah County is chalk full of Mormons, who believe that they have the one true gospel and only they can save humanity from themselves/Satan/god. The stated policy for every treatment facility I have worked for has been that employees should not proselytize religion to their patients. And yet, I have seen countless instances of Mormons breaking that boundary. Overtly, and unapologetically.
At any rate, I actually agree with the policy. I think it's a good rule of thumb for healthcare professionals to avoid pushing religion (and atheism!), politics, pseudo-science, etc. on the vulnerable people in their care. But some facilities take it a little further. Not only do they discourage proselytizing of patients, they also recommend that patients do not make any changes in their religious views while in treatment.
On the surface, I can see this being a good rule of thumb as well. But I have seen a number of patients who have been hurt by religion or who simply don't want to follow the religion of their parents, and the facility where I currently work encourages them to stick with it. I have seen therapists even refuse to talk to their patients about their thoughts on religion and how it affects their relationship with their parents. Even just encouraging the patient to set a boundary with their parents would have helped smooth out certain situations. But no, that would upset the parents and we can't do that, because the parents are the ones who pay the bill, and let's be honest, the parents are the real customers here, not the patient who is depressed because his parents are controlling every aspect of his young adult life. No, no, religious views (of the parents) must be protected!
Part of the issue here may be due to the fact that Religious Trauma Syndrome is not yet recognized by the scientific community at large. At least, it isn't included in the DSM-V (the go-to diagnostic manual for psychiatrists). Religious trauma can fall under PTSD and similar diagnoses, but as is evident by the way many people avoid talking to patients about religion entirely, I think it would be helpful for it to be it's own category of trauma. It would provide a context for professionals to talk to patients about the very real emotional harm leaving religion can cause.
Imagine a person feeling controlled and manipulated through religion for their entire lives. The people they trust most use religion to coerce them to do or not do certain things. Imagine the religion tells the person not only can they not have sex, but that if they touch themselves sexually that they will be separated from their family for eternity. If it was an abusive parent or spouse, a therapist wouldn't think twice about helping the victim out of that relationship. But religion gets a pass. Religion is presumed to be a net good and way too big a can of worms to open. I have heard Mormons tell suicidal LGBT people that staying with the Mormon church is good for them and necessary for them to be happy. All they have to do is either marry someone they are not attracted to or remain celibate for their entire lives. After all, their family is at stake. Why would they risk losing their family for eternity? Do they want to make their mother cry forever?
To be clear, I'm not advocating that therapists push atheism on a patient. That would be just as unethical as pushing religion. But I am advocating therapists being willing to walk a patient through their own beliefs and encouraging them to stay true to their values rather than the values imposed upon them by parents.
Like many people, I found peace of mind and came out of depression by leaving religion at the curb. Staying in religion would have prolonged my depression. Thank god I'm now an atheist.
BONUS MATERIAL:
Dr. Darrel Ray on religion and sexuality: