Sorry to hear you're weathering some rough seas. Though I'm still hit by episodes of depression, anxiety, difficulty concentrating, mood swings, etc, I've now established a library of activities that help me get through an episode without reacting to it much. These days I don't even label it as anything - no matter how bad it is - I just recognize I'm having an off day and reach into my bag of tricks to help me get through it until it passes. This has proven invaluable in not letting myself sink too deep and shorten the duration of a wave.
It wasn't easy getting to this point and it took many months of concentrated effort to create a mental foundation I could build on. It started with positive affirmations, even though I've always thought such things were silly and stupid. 'I am loveable, I am happy, I am free' - I didn't believe a word of it at first - all lies! - but I've finally started to believe I actually do deserve a good life and that it's worth fighting for.
I also used to look at myself in the mirror (a struggle in and of itself as I did not like looking at myself, I was too ugly as a person) and then smile. It was forced, it felt completely unnatural and looked more like a snarl than anything else, but over months it actually started to feel natural and even a brought a tinge of happiness - maybe - when I did it. Now just the act of smiling short circuits a downward spiral and helps prevent a low from deepening too much.
I then began painstakingly recultivating a sense of enjoyment and pleasure in things I used to like to do. Most recently, I've regained the ability to lose myself in a good book. It's been 10 - 15 years since I've been able to do this. When I sit down and open the pages, hours can now pass by in a blink. By the time I set the book down, I've almost completely forgotten that I'm feeling down.
As you know from this and other forums, these waves pass and there is a better tomorrow. And you have tremendous power to make that tomorrow be what you want it to be.