This is a natural part of the creative process - you get stuck, or burn out, and start looking for other ways fulfill that creative hunger. Honestly the best thing to do isn’t to force yourself to work on a single ‘dream’ project, it’s to have many dream projects and bounce between them. When your personal finances aren’t on the line (you’re not working on that game to put food on the table) - whatever keeps you working is always the best, even if it isn’t always the same project.
The same thing even happens in large studios working on huge AAA projects. You come on to a new project, it’s new and exciting, you can’t wait to add X and Y to the game. You stay late without anyone asking because everything you do has to be perfect. A year later you’re bored, you don’t care anymore, you leave at 5pm on the dot, and you just want to move on to something new and exciting. By the time the game ships, you’ve convinced yourself it’s garbage and people are going to hate it. you’re off to the next project, and the cycle starts over!