Time to get one twice that size, I'd shred it too 
But with respect to your trainer "they grow out of it by 2-3 years" is full on ridiculous.
But with respect to your trainer "they grow out of it by 2-3 years" is full on ridiculous.
Based on the pictures, you need an XL, they aren't going to want to curl up until next fall or winter, they need to stretch and and still be on the bed or they'll just lay half off....or over in your case. We have to have 40-44" bedsIt’s actually a large! He does fit in when he’s not rolling around on it lol! Plus I have a Kuranda for him. I will probably get a mattress type bed though as he tends to like to stretch out rather than curl up. It was more of an experiment in seeing if it would survive.