Been down in deep depression and survived .... and even if sometimes things get a little tough, if I really think about it, never nearly as bad as the worst days.
I understand the riding part---cracked my collarbone, had to work, had some health issues, then I didn't want to ride in the rain with my shoulder only half healed .... and that bike ride, which makes so many other things better, is always "tomorrow."
it will be okay.
I have been through enough cycles of this crap to know that. Unless we completely, deliberately, actively act to surrender, we come through ... and because you have some faith, and some confidence, and some experience of success, you will come through better.
The biggest change between now and when I started fighting my way up ... now when I go through longer down periods I am okay with that (just as you said ... can't fight it all the time, some days just have to accept and acknowledge to overcome.) I tend to get less stressed when things take longer to resolve, because I have been through it so many times, and I Know they will get better, and that the general trend is always better and better.
You are on the right path and doing fine. Accept that life can be frustrating and complicated and scary sometimes, and soon you will start to regain your positive attitude and things will seem a lot less severe.
Because this is a public forum I won't get too deep into the faith angle, but that is one place you can always find strength, if you let yourself. How you do it doesn't matter ... I don't care if you seek support from an old pizza box or a burned out television, or a book or an idea or a group ... let it work for you in the way it works best for you.
Glad to know you will be back on the bike soon.