Emotions taking over

For the past weeks I have been on a real internal emotional rollercoaster and can't seem to calm down. I'd go out to get out of a really down mood only to be met with the feeling that I could burst into tears in the middle of the outing while I am actually smiling and pretending to be ok. That in itself tires me...imagine wanting to cry so much, but pushing yourself to be smiley and social. I wonder why do I always get this urge to cry when I am around my closest friends...but when I am alone I'm unable to? Why do I even want to cry? And why do I want to smile at other times? The ups and downs tire me...sometimes I wish I could just stay happy or sad...one or the other. Just stick to one feeling for God's sake! But I just cant seem to. I feel sad and automatically my need to always switch that back to "happy" kicks in so I start looking for what will make me feel better, whether its going with my mum to run errands (just so I could drive the car), or a chat with a close friend, or reading my book (which involves people in really bad situations so I would be perfectly fine in comparison so would feel silly to feel bad), or listen to songs I like in bed and sing them in my head. Then when I finally felt happy...my mind manages to trick me by reminding me of what it is that's upsetting me so I soon start to slip back into saddness or I manage to catch myself by switching the TV on. I guess being a little free at work these days and not having IPM to keep me busy in every waking minute has given me the time to depress myself, and linger over things that I simply cant change... Mai, face it...everything that is bothering you just needs time to fix itself, you have done all you can, and just use your common sense and intelligence because you know all this is because you are letting your emotions take over. This is what I tell myself over and over, and I can be extremely practical when I want to be...so why dont I WANT to be practical now?