I know I push too hard when I cut. I also walk hard & wear out heals, chew hard and have TMJ. I think I just like to live at full speed but now it's getting serious... There's actual grooves in my self healing mat. Last night when cutting out pieces for mariner's star, sometimes the fabric would sink down into a groove in the mat - very messy. The edge of the fabric would fray as I pull it out & didn't always cut all the way through. And yes, I am using a fesh blade in my rotary cutter. Is there any way to save this mat or is it too far gone? How long should they last? I've had this one for at least 10 years.