Great dreams and greater fears

Last night I was kind of wondering to myself if the path that I have set for myself is the right one for me. Apparently I was in one of those contemplative, 'what does it all mean,' states that I get into every so often. Usually those states of mind are partnered with a negative sense of self and anxiety. On top of that my mind's inability to shut off is creating an issue with sleep thus further making me ponder and ruminate. The anxiety was exacerbated with the break-in but I also knew it was coming because it has a pretty consistent cycle. The mood I was in gave me that desire to want to just crawl out of my skin or drop everything and leave. I know when I am unhappy with myself when I start to think about putting all of my stuff for sale on craigslist and taking off in my car for one of the coasts. My desire to get out of town doesn't really have anything to do with getting robbed, it more so has to do with the reality I am creating for myself, the positions I put myself in and my penchant for anticipating disappointment. 
I know I talk about this a lot but I continue to frustrate myself with my struggle to stay positive. GRRR, why is thinking negatively my go-to response? Why do I find comfort in being angry or irritated when things stress me out? I sometimes wish there was a switch on my brain that I could turn on when I start getting into those moods that would just flood my brain with positive thinking and excitement. The funny thing is that when one area of my life isn't going the way I think it should it quickly invades all the other parts of my life and then I begin to worry about those parts too. 
I've got plenty of things to be excited about like grad school starting soon, a boy that is just way too patient with me and new adventures. 
Someone just needs to grab me and shake me. If I do that to myself it just kind of looks like a seizure and doesn't get the point across.
Introspection is a bitch.