I'm sorry that your son is experiencing some pretty turbulent times right now. I'll try to disentangle some of the issues.
With regard to the grief surrounding the loss of his brother and grandfather - first let me express my condolences to your entire family. Second, I'm glad that you're having him go through counseling right now to address these matters. Third, the grief may or may not be related to some of the OCD-type behaviors you describe... it is not uncommon for complicated bereavement to lead to other mental health issues that might have been laying dormant. The added stress of grieving the loss can sometime lay bare those issues. Fourth, if his behaviors/feelings are truly OCD - there are very effective treatments available to address it.
Please understand that it is both inappropriate and unethical to diagnose over the internet. That diagnosis can only be made by a Licensed Mental Health Professional (LMHP).
With regard to the OCD and depression:
Research has consistently demonstrated that treatment plus medication is more effective than medication alone or treatment alone for depression and/or anxiety. Further research has shown that Cognitive Behavioral Therapy (CBT) is the most effective form of psychological treatment/intervention - particularly in dealing with mood and/or anxiety disorders (like OCD).
A licensed psychologist/psychotherapist with specific training in CBT modalities would be able to address your concerns. I would encourage you to find a licensed mental health professional with whom to work, employing CBT. If you are addressing OCD, a specific form of CBT is called Exposure with Response Prevention (ERP) [Lots of letters, I know... sorry.] ERP has been found to be as effective or more effective than traditional medications for OCD. Be sure when you speak to a possible licensed mental health professional that s/he employs CBT techniques - not just "influences from CBT" or "an eclectic approach."
With regard to medical treatment, many/most physicians appear to begin with a Selective Serotonin Reuptake Inhibitor (SSRI) to treat anxiety. Because I am not an MD, it is beyond my purview to address medication concerns, however.
Again, the mantra of years of research says: medication or treatment alone is not as effective as both working in tandem. Some research has also indicated that insight-oriented talk therapy is counter-productive with some forms of mood and/or anxiety disturbance... it actually exacerbates the condition(s) [This is especially true with OCD]. So, seek out a CBT therapist who will provide targeted, efficient, and effective therapy - not someone who signs you as a "lifer." If you're going to a therapist for years, something about the therapy isn't working.
Your psychiatrist *may* know of a CBT licensed mental health professional. Please make certain, however, that they employ CBT practices.
If your current counselor is not CBT trained and proficient, I would ask to see someone who is. Your son can continue in therapy to address grief issues (provided it is not contraindicated), but traditional talk therapy to address OCD can actually make the condition worse. Try to locate a professional who has expertise in adolescents and OCD. (The specific sex-related obsessions you describe, for example, are not at all atypical of adolescents with OCD.)
Thanks. I hope you're well and that this was helpful.
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