To Ride or Not to Ride...

I'm supposed to be leading a group ride tomorrow. With temperatures supposed to be in the 70s, it's sure to be a fantastic day for riding.

So why the conflict?

Simply put, it hurts to breathe. I'm fairly sure breathing is an important element of riding a bike. I've felt this cold coming on for nearly a week now. Up until this morning it has been so mild I could deal with it. Then I rode really hard in Spinning class this morning. Before I could even lock the Spinning studio door the coughing fits had started. Now my chest just hurts and my breathing is shallow.

Yet, I feel like I should ride tomorrow. The group needs me there, because how will they possibly know how to ride without me? :)
And I don't want to give up an important training day. How will I make up for lost time?

What to do, what to do...