<human>: So I seem to have this problem, where I'm either extremely motivated (to the point that I'm obsessed with something) or I'm not motivated at all. I'm currently experiencing this with a volunteer position I took on with a presidential campaign last Fall.

When I started I literally was in my local office upwards of 65 hours a week. I was given more and more responsibilities, and I eagerly accepted them; I'm now in charge of volunteer operations for an entire county (still an unpaid volunteer myself). From September until early February, I literally devoted 95% of my time to the campaign, to the point of neglecting my personal and academic life. In early February, I was informed that my boss was getting a promotion, and that she would be moving to another field office. During the transition phase things fell apart. I didn't get a paid promotion that had been promised to me for several months, it instead went to a political appointee (someone who knows someone important). When that happened, I literally lost all my motivation to work for the campaign. Since early February I've barely been in the office for more than 2 hours a week, my team of volunteers is slowly yet surely falling apart, and my motivation to go back dwindles away even more with each day that passes.

This seems to happen with any longterm project that I take on. Whether that be learning a long and complicated piece of music (I play the Cello), dieting/losing weight, etc. I can't seem to moderate my level of motivation and commitment. It's like I have an on/off switch; either I'm completely gung-ho or I don't want anything to do with the project in question. So Reddit, can you give me suggestions on how to stay motivated without becoming obsessed?

Could you distill the essence of the text into 1-3 sentences?
<bot>: I'm either completely committed to a project (to the point of obsession), or I want nothing to do with said project. How can stay motivated without getting obsessed?