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He’s suffering from depression

“Clinical depression is one of the biggest killers of sex drive in men,” says Vancouver, BC-based sex therapist David McKenzie, PhD. Men of all ages, even teenagers, may experience much lower sex drive when they’re struggling with this mood disorder.

You can: “Remember that clinical depression is a physical illness and not a character weakness,” says McKenzie. The key here is patience, especially after he seeks treatment—while antidepressants are very effective in treating depression, they can also contribute to low sexual interest. Your partner may want to speak to a doctor if he notices severe interference with his sex drive. Learn some proven depression-busters from those who have been there.