How do you manage with mood swings/mood instability?!

Well, for the depression theres teqniques you can learn in therapy.

but for mixed episodes (depressed/manic) the only thing that helps is meds...

First of all my friend, you have my empathy due to the self harm issue there, as I have scars all over my right arm. I haven't cut in over a year now !......
I need to know your situation really, have you ever used drugs or alcohol ? You may have Bi-polar disorder, but this can be made much worse, or even triggered by drug or alcohol use, a symptom of the substance you could say. Are you on any medication for depression and anxiety ? as believe it or not, those pharmaceuticals don't work to relieve your symptoms, and they have a negative biochemical effect on your whole system.
I used cannabis and alcohol heavily to subdue the feelings of depression and self harm, which made the situation worse. I was trying to gain mental stability and clarity, which I am sure you know are not at all in balance when suffering a mental issue. And I am sure there is one issue bugging you right now.
I managed to gain back my mind through uncomfortably quitting the substance use, and replacing it with meditation while listening to "bin aural beats" (search on youtube), which stimulates the "pineal gland" and therefore naturally producing "melatonin" a happy brain chemical. Believe me after even ten minutes of listning with your eyes closed, you will not want to hurt yourself.
I also began to utillise exercise as a healing tool, as it also produces happy chemicals. Go for a walk and enjoy the scenery around you my friend. Nature heals.

It gets better, gradually day by day, your self asteem WILL start to rise.
And stop the thoughts, ..the negative thoughts upon the self, will act like a virus and corrupt your whole being, instead embrace your life as a spiritual journey both good and bad....AND YOU ARE NOT ALONE!

I hope I have helped, and can help in the future.

Jordan
jordthewizard@hotmail.co.uk

university of life