Yes, I totally relate OP.
I really thrived during the first lockdown. I had lost my mother the year before and my extra marital affair had ended and I'd just come back from two months overseas, so I felt like the lockdown was the perfect opportunity to heal and go inside.
I worked out 5 days a week, finished a novel I was writing, did some freelance writing and watched TV shows I loved and read. I felt really happy.
As this has dragged on, I've started to become despondent. I feel like there is nothing to look forward to day after day. I feel often like a young child or an old woman because I don't feel as though I have any autonomy over my own life.
I am working from home and doing a course so I am still being productive (although exercise has dropped off totally.) I've also completely lost my appetite. It's like I've even become bored of eating? Whereas at first eating was one of the few distractions and pleasures I felt I had.
I know part of why I feel bad is because I had problems before hand that have been allowed to fester due to lockdown. I have some troubles in my marriage, I have things I want to do, and I feel like this has taken some time from me that I won't get back.
I find myself panicking about the future...death, whether or not to have children, what the hell to do with my life. I really am not happy living like this day after day and often feel like a trapped animal.
I'm blessed in a lot of ways...at my father's home which is beautiful, working, savings, a relationship...but I feel alone, isolated, alienated and like the momentum has been snatched out of my life.
I've been escaping into fantasy a lot which has been a huge comfort, but I also then find myself feeling jealous because it sparks desires for adventure in me that I cannot pursue.
I just feel like I live in a dystopian novel. Not every day is bad. Or every week. But as an overarching life I feel like this is not living. I'm early thirties but feel often like my best days are behind me. I look back on all the things I used to do and it feels like a 90 year old looking back on being 20. I'm terrified of frittering my 30's (supposedly one of your best decades) away on not being able to do much of anything. It feels like a waste and I feel robbed and angry which then settles into depression.