You're right. Getting out of your "comfort zone" is something for you to decide. No one else gets to decide that. ESPECIALLY for sex. It seems to me that the benefits of "getting out of your comfort zone" are to increase the richness and diversity of your life experience, and to grow more as a person. But grow, how? What are your values? How exactly do you want to grow? Your growth will not look the same as somebody else's growth.

My therapist gave me great advice. She told me to list my values; words that represent what values are most important to me. In any situation, when deciding what I should do, I remember what is most valuable to ME, and if I'm moving further in the direction of my values, then that's good. If I'm moving away from them, then that's bad, obviously. Doing risky things doesn't necessarily mean they're in line with your values. That fear you're feeling may be because it's actually not a good choice for you, if it doesn't align with your true values.

She also told me that pushing yourself only works if you have adequate preparation and support. If you're hiking up Mount Everest with no clothes, no food, no training, no water and no friends, then it doesn't matter how hard you push yourself. You need to take care of yourself first in order to succeed.