Last season my running partner was a lot faster than me and I always wondered why she ran with me. I read this in an article titled: '27 things your running partner won't tell you'
#27. Even if a training partner is faster than you, don't discount yourself. Chances are very good that person admires something about you: Your positive attitude, your ability to make compression shorts look good, your persistence…whatever it is, keep it up. There's a reason they're still training with you, you badass.