Hello Gigi1981,
Throughout my years of practice as a psychoanalytical psychotherapist, and personal experience, I'd first emphasize that you should find yourself help, even if it happens before he does. Living with someone who has, at minimum, depression wears us down as we are induced with their intense feelings which interfere with our own psyche. Find some support such on places like this, psychotherapist, good friends, all and anywhere you can.
For your husband, depression cannot be treated months at a time every time something goes bad. The worse time for someone depressed or has a chronic mental illness, and the majority of people, to quit therapy is when they get better. It's a trick that a good therapist should let you guys know about. Things will start to get "better" a few months into therapy and if you leave you're setting yourself up for failure.
Medication is a scary thing, especially with everything that's going on. If he's totally against medication, don't push, but make sure he gets into weekly therapy or psychotherapy.
One of my biggest concerns was when you said, "I will give it some weeks to see how he improves and most of all, because I do not want to make a decision right now that we may regret and that may make him worse." I feel that you've had this thought and gone through this every year. Seeing what you're going to do, but giving him a few weeks to get better and most of the time he gets better within that time frame. Something is going on there between you two that a professional/support could help weed out because it's a sign of a destructive repetition/cycle between you two which will keep the both of you stuck where you don't want to be.
Let me know if I misunderstood or didn't say anything clearly or if you have any questions.
Psychoanalytical Psychotherapist: Online and In Office Psychotherapy Sessions.