Specifically clinical depression?

My husband and I have been married for 7 years and we have 2 babies. He works quite a lot in a stressful field (digital marketing) and has always struggled with imposter syndrome (feeling like a fraud/not good enough).

In the past 6 months he's developed signs of clinical depression, minus suicidal thoughts. He has little to no desire to want anything, doesn't look forward to anything, always feels tired, low sex drive, feeling hopeless, guilty. I'm supportive and understanding, but his low sex drive has hit me particularly hard because I have my insecurities and automatically feel rejected even though he's made it clear to me it has nothing to do with me or my looks.

Today he went to the doctor to check his testosterone levels just in case. But likely that isn't the issue. He just feels really low. The next step is booking an appointment with a psychiatrist to get formally diagnosed.

He really hates the thought of going on antidepressants and wants to go the natural route.

How do you handle it in your relationship? How do you support?