Black Wolf, both George Stubbs and Marine Oussedik are excellent artists. There are many, many awesome, talented illustrators.
I love Kim McElroy, Leslie Harrison, Donna Green, Gladys Brown Edwards, C.W. Anderson, Wesley Dennis, Sam Savitt, Sveltana Novikova, Marcia Baldwin, Judy Larsen, Bev Doolittle, Robert Bateman, Carl Brenders, Lydia Kiernan ... um, just to name a few. ;0)
Something you can try... this will take practice but if you do it every time you have bad thoughts, you eventually get into the habit and it helps shift your mood a lot...
Every time you have a bad thought, IMMEDIATELY start thinking of things that give you joy and happiness... one of my things is horses (of course) but also Baskin and Robbins Jamoca Almond Fudge ice cream, Music that uplifts me (example Katrina and the Waves 'Walking on Sunshine' or Walk the Moon's 'Shut Up and Dance'). Also try doing a physical exercise. You could dance to some music. Or do something like 10 jumping jacks or lifting some weights (you don't have to have official weights... a jug of laundry detergent or water will do) or go outside and go for a walk or jog.
Don't listen to this religion's doom and gloom. It's a pile of crap. Every negative connection your brain makes, it needs at least 12 positive connections to negate the one negative one. Force your brain to make positive connections. Just Do It, Wolfy! :0)