You have to keep in mind that, in some sense, empty space is nothing. So it is nothing that is being bent. Properly understood, curvature of space-time has to do with how we measure time and distance. Roughly speaking, it is those imaginary straight lines from Euclidean geometry that are being bent.
Nikola Tesla thought so too so you may place me in the same catagory of "what"?
Tesla also has the reputation of being something of a crackpot.
Even further, I believe several well known scietists also published around the time of the starlight refraction event predicted by Einstien that jumping to the conclusion that space itself was bent by gravity was a bridge too far when the light itself being bent could just as easily be the explanation.
Well now you owe us an explanation of why you think "space being bent" and "light being bent" are different things.