Everything in your life will change how you write. How you manage your thoughts and emotions will determine which way your writing goes. Channel it and use the energies for greatness or allow it to take you somewhere less majestic.

I think it's just like anything else you feed your mind. If you watch depressing things when you're depressed, it may not help. Music is definitely that powerful. So maybe find some uplifting songs to listen to. The brain needs a healthy diet to create balance.