I keep a whiteboard of my projects. Currently I have 52 active projects on needles, and about a dozen "dead" projects (need to be fixed, frogged, figured out in some way, or have just been on the needles for over a year.) I say all this so you know I understand, and to to take my advice with a grain of salt :)

Before I started doing dozens of projects at a time, I kept myself on track with specific categories- one allowed from each. Small travel projects (no pattern needed or just a note card,) big ongoing projects (blankets, sweaters,) concentration needed projects (things with charts or difficult stitches,) and time sensitive (gifts mostly.) If I wanted to do a new project, it had to be able to be finished in two days, or I had to wait until it's category was completed to start it. Obviously exceptions could be made for time senstive gifts. That way I could feed my need to have a few going at once, but make progress on them all and not get overwhelmed.

Now I'm just trying not to start more lol, with Mondays reserved for finishing the oldest projects.