If all the What Not to Wear reruns I watched in college taught me anything, it's that things don't have to match — they just need to "go." Just like how your belt doesn't have to be the same color as your shoes, your walls don't have to match your curtains, etc.
To me, figuring out how to combine 1) what "just goes together" with 2) just a little color repetition is key to making a room that feels pulled together but lived in. You don't want everything to clash (although it might come close), but you don't want a catalog either.
I find some of my favorite examples of fearlessness in combining colors in contemporary, design-savvy French homes (Image 1). While you might not be ready for, oh, cabinets that are five different colors, something like mix-and-match pillows can add a more manageable dose of carefree color.
Images: 1. Rebecka Oftedal for Design*Sponge 2. Samantha Pynn via Mix and Chic 3. Kaul Production via Bolig 4. James Merrell via First Sense 5. Design*Sponge