If you are currently unhappy with working long hours for minimal compensation, I don't think starting a job in which is try to sell things you made on a platform like Etsy will make you happier. You will find that consumers seriously undervalue the labor that goes into most handmade products (most consumers are too used to the dirt cheap prices of the same goods when made in factories paying next to nothing). Etsy and other platforms that make it easier to manage the financial aspects of such a business can also be exploitative -- search results often make it hard to break through the noise, any kind of custom order will put you working with demanding/unreasonable people (not everyone but all you need is one really PITA customer to ruin your month in this kind of job). And at the end of the day, you will almost certainly make less than you expected or wanted, plus be stuck figuring out stuff like payroll taxes (assuming you make enough to have to pay them, it's a bit of a catch-22).
But if you now make 45k and are okay going to like 25k, I'd look into quitting and moving into a contract position that is part-time, allows you to WFH all or part of the time, and has flexibility with hours. Either at your current employer or in the same field.