Hello Ems, when somone becomes depressed, their partner/spouse is unsure of what they should say, to try not to make the other person more upset with their lack of knowledge or understanding of the current situation so they decide to not make themselves available, this may not be a lack of love but a safety measure, not to cause an argument.
What may be going through his head is many options, what if I say this or that, will it help or make it worse, so their decision not to make any comment seems like their safest option.
You can't blame yourself for feeling this way, nor can you necessarily put any guilt on him because both of you are doing exactly what you want need to do for survival, in other words, you can't keep chasing him when he is inexperienced, but now both of you need to talk with your doctor.
There are a couple of suggestions to first of all, help him, is to mention the Men's Shed and secondly to say that you have made a double appointment for the doctor, then they can direct either of you or both, into the direction where you can receive help.
Ask them about the 'mental health plan', this entitles you to 10 Medicare paid sessions for the both of you.
Best wishes.
Geoff.