Start a hobby, preferably one that's outdoors as nature always cheers me up. Maybe right a blog on your past, current, and future life on changes you're making and what other like you can do.
Also, maybe consider coming up with an exit plan for leaving your job. Take this with a grain of salt but save up 1 years basic living expenses, find a part time job instead, then 100% into a business you could build. However, while saving the 1 years basic living expenses, you have to spend the weekends learning and building a business so by the time you've reached your goal you'll probably be ready.
Also, maybe look into the book "The Miracle Morning" by Hal Elrod, it's changed my life. If you're not a fan of reading, tldr, the book is about life SAVERS - Silence (meditation), affirmations, visualization, exercise, reading, and scribing (journalling). All of this can be done in as little as 6 minutes 1 minute per letter. However, it's recommended to do 1+ hour of it divided somewhat equally with slightly longer meditation and exercise and shorter affirmations/visualization.
Maybe Mel Robbins 2019 mindset reset YouTube 35 day challenge could be good for you. I loved the first 9 days, I just stopped watching cause I didn't need it.
Peace!