What do i do? anger and depression?

i am a 15 year old girl and my parents have been trying to get a divorce for 3 years now and its beem messy and has mixed up and partiallu ruined me and mu brothers life because of what they put us through. Now i have so much anger built up inside and i also have depression. the negative thoughts i get from depression are of the norm and everyone says to try and think positive vut i just CANT ! i just cant i try soo hard but i just cant be positive when im having an episode... i need help and i dobt know what to do... i trued talking to a councelor at a church about my anger and short temper but it didnt help at all.. they told me to relax an breathe but i CANT DO IT!! i feel so frustrated and angry and sorrowful sometimes i think im becoming a psychopath because i just cant feel anything but sorrow and anger towards the world and i wanna cry but something inside me says that if i do then i will become weak and not as hardened to the bad things in life. Since i was little all i wanted to do was become a rogue like in Dungeons and Dragons, and i feel if i cry than i cant become like that (and by that i mean strong, flexible, sneaky, ruthless etc.. but forget the pickpocketing) so i desperately need help and i just poured my soul into typing this PLEASE HELP what can i do for my anger and depression and what will happen if i absoloutly hold everything in ???!!!