Silicone will hold up under a lot of abuse — but not infinite abuse. A small tear in a silicone toy will very quickly become a big tear, and then a bigger tear, and soon after that your silicone toy will become two silicone toys, neither of which is very usable. So keep it away from anything sharp that could tear or scratch it. (That includes the cats — it’s been reported that cats adore silicone sex toys and think they’re the best cat toy ever.) And don’t bend it too outrageously; silicone is pretty darned resilient, but not infinitely so.
Blowfish.com: “Caring for Silicone Toys”.