I don't think you're going crazy at all. Life with uncertainty is difficult. We like to be productive and have some kind of 'measure'. We like to see progress. In lockdown, we don't know how long it will be for, we don't know when the next one will happen and it makes it difficult to plan.
A few years ago, I looked after my mum during her cancer journey. For three years, I lived this kind of life. Unable to work. Unable to plan. As everything revolved around health decisions for mum. I felt every single thing that you are feeling now. Would I be able to go back to work? Would I want to? I felt like I was treading water while everyone else was living, and going on holidays, and getting promotions, and going out.
So, stagnating. treading water. Acknowledge these things for what they are - crappy, but they are temporary. on the days you feel good, and the moments that you are enjoying, - really take note of the good, the fun and the joy! be present and savour the chocolate (insert treat of your choice if chocolate is not your bag!). Your brain deserves the good chemicals as much as anyone else's.
I've taken to watercolour painting this year. I am incredibly bad at it - like, I cannot create a picture that I try to... but somehow - adding colour onto a white surface and sometimes accidentally creating a flower, or a tree... it's such a wonderful feeling! it surprises me, how it is - to create without purpose - the way that kids just draw, without judgement or intent. that has helped me quite a bit.
I wish you all the best and want you to know that you are not alone in your feelings during this pandemic. I had those feelings in 2015-2018 (pre-Covid). I did colouring-in books back then, with mum. it was good for both of us actually.