hey Neonevil. I am really glad to hear that you'll be at good hands soon. But, from my experience, medication and psychotherapy cannot necessarily change the way you view things. Medication will be very helpful in terms of allowing you to better take control of those more depressed moments, while psychotherapy will allow you to figure out what's caused you to depressed. On the other hand, thinking and acting positively is something that can only be done through you.
As a person fighting against Major Depressive Disorder, I see clinical depression as the less severe form of schizophrenia. While the reality that a depressed patient accepts does not deviate from the truth as much as it does for a person with schizophrenia, their perception is nonetheless heavily influenced by their emotions and thoughts, and thus can often veer away from the truth. For example, a depressed individual is more likely to see a very brief change of expression in someone's face as a sign of deception or even contempt, while the others may choose to ignore it (as they often should). Patients suffering from depression are much more wary around "signs" that their correspondents exhibit while being among them, and they are also more likely to make something negative out of what they notice than necessary.
Understanding the aforementioned and accepting it as a fact - which it is - is the first step to treating your negativity. It is naturally easier said than done, but you will learn through your therapy process that a lot of your opinions and thoughts can often be misguided from the truth by your strong, negative emotions and thoughts. This does not make you stupid or naive compared to others, however; it only means that your depression has become significant enough to start affecting the way you see things - something that can happen to anyone, regardless of their knowledge power or experience.
Once you have overcome that barrier of understanding your situation, you want to do little things that will help your mood stay positive. First, try to eat as healthy as possible. While I am no biology major, eating a lot of junk food can more often worsen your feelings than improve them. Sure, indulging yourself once in a while is never harmful, but try to eat as healthy as you can throughout most of the days in a week.
Second, do a lot of exercises. I don't know what your daily schedule looks like, but a minimum of 30 minutes of good cardio exercise for five days a week is as good as taking a regular dose of antidepressant. If you are not a huge fan of cardio workout, then stick to weight-lifting. I personally am more of a weight-lifter than a runner, and while weight lifting does not produce the same physiological benefits that running can produce, it nonetheless is very effective with improving one's self esteem. It certainly doesn't hurt to see how more muscular and defined you are after each month
Third, smile and laugh as much as possible. Always have an access to something/someone that can make you laugh. Laughing produces hormones that will make you feel more relaxed and happy, regardless of how upset you were before. Laughter - to our body - is a physiological painkiller that we have adapted to use. It's like when cats purr; purring causes the same, comforting sensation in cats that laughter does for us. If you don't think you can manage a laugh, at least smile. Often times, I find myself thinking about something depressing, but all it takes is a smile to turn all that negativity into positivity. I know it sounds real silly, to suddenly burst out into laughter or to force out a smile when you are feeling real down and having negative thoughts. In fact, it sounds almost too silly to be true. Well, you'll just have to take my words for it, but, based on my experience, trying to smile or laugh when I was feeling really down did wonders. It helped me switch back to thinking positively - if not realistically.
Anyways, I hope this will help you battle through your negative thoughts. Just send me a message if you need anyone to talk to, or have any question you'd like to ask. You can also read about my experience with major depressive disorder on my blog, http://stevenksaid.blogspot.ca
Wishing you all the best,