It seems to me you would need to adjust your goal. If your goal is to finish your current project, then you might have difficulty interrupting the flow. If, on the other hand, your goal is to work on different multiple projects, and to enjoy them more, then your goal changes. You have more freedom. It really is about freedom from being enslaved by old habits.
When I started quilting, I finished each project before starting on the next. Then I made my son and DIL each the same quilt from different fabrics. Then I added two more projects until now, I'm working on anywhwere between 5-8 projects at any given time. A block or a row here and a block or a row there. I enjoy it more when I have lots of variety. At any given time, I'm working on a bed quilt, a table runner, a charity quilt, an applique project, a BOM, etc. I don't finish any one project as quickly as I used to, but I enjoy the process more. Enjoyment is my goal, not completion.