Over Analyzing

Staring at my blank page once again, I have all these thoughts that I could put out there but then I find myself dismissing them before I even get a chance to start.  So I'm going to try to just start typing and see where my thought process leads me.

I think that the biggest issue I have is that I am constantly over thinking everything.  I usually a very optimistic person but really in my head I'm always thinking worst case scenarios.  It's a constant battle that I have with myself at least twenty times a day.  Does anyone else have that problem? And does anyone have that problem to the point that it effects the relationships you have with people? I feel like I'm constantly thinking worst case scenario when the smallest thing goes wrong.  I'll give you an example, you're out with a couple of your friends, you leave to go get another drink and when you're coming back to the place where your friends are you see that they're having an intense conversation but as soon as you get within ear shot they stop talking.  You ask them what they were talking about and they say "o nothing, just stuff about work."  You want to believe them and for the first couple of minutes you do. Until you start thinking about all the little details, the body language, the possibility that they could be really texting each other, "the vibe" they are now sending you.  But are they really sending you a bad vibe? Or do you just think they are because you think they were talking about you behind your back. You're able to get through the night with it just rolling off your shoulders but, when you get home or wake up in the morning, you can't help but overplay the events of the night into the smallest details and analyzing everything, (at least the parts you remember). 

Now I don't really have this problem too much anymore because 1) I don't go out very much anymore and 2) when I do it's just me and one other person so the chance of them talking behind my back is fairly slim. Unless.... they have another personality that I don't know about. I go through things like that on a daily basis, with my co-workers, my family, my boyfriend,  I'm just constantly over-analyzing everything.  And since I'm usually optimistic I try to tell myself that I'm wrong and that the worst case scenario is simply ridiculous but then I go back to the little detail that started me on the analyzing in the first place.  It's a vicious cycle but sometimes I wander if maybe I have another personality.  Either way, it's effecting some of the best relationships I have and something needs to change.

I putting this question out there feel free to ponder, feel free to comment, or/and feel free to never read this blog again because by the end of this you feel that you'll never get that 15 minutes back in you life.
How do you fix over analyzing your life without over analyzing?  Is it possible without going to a shrink?  Or should I just tell myself that it's who I am and the people in my life will just have to be patient with me if I come up with ridiculous scenarios when something minuscule happens?