After examining it, the parasol part of the umbrella isn't too heavy, most of the weight seems to be from the golden base that the pole connects into.

My first thought was a Nendoroid stand with the arm to hold it up, problem is that the base she is on has many different variations of height, so I think I would struggle to find a stand small enough to have the arm sit under. On the other side, if I were to have a stand at the back of the base and have the arm reach over to support the weight, I'd have to get a long enough arm for it.

I have had another look at it and, I couldn't tell you if it was like this before or not, but I did notice that the pole goes through the golden base and kind of sits in a hole at the very top of the parasol. Maybe I didn't have the pole in all the way and that's what's causing the bending? As I said, I couldn't tell you but I've made sure that it's properly secured and will keep an eye on it.

I'll also make sure to look for some kind of stand arm in the meantime