Hi pauly22,
Sorry for you . Man, what a nightmare sight !
To reinforce the greehouse, you could set it against the house so that the wind is not so strong.
You could as well, put the greenhouse near or under trees, or have trees around it to cut the wind .
But well, if the wind wants it, it will have it .
The only way to make a greenhouse stronger is to make it heavy - It is not really feasible unless bought for that purpose.
My garden house - to store shovels... - is made of corrugated iron panels that I assembled myself with a wooden framework . It is really unbreakable.
I had clear plastic/polycarbonate panels for the roof and had to replace them with corrugated iron frames because the firsts got blasted by the wind, snow and rain .
I don't know if some of you have tried the thin iron garden house that you can buy - they are not that much expensive ... Well, forget about them, or you'll get the same troubles.
My three neighbors found their own totally opened and flat in the middle of their gardens - blasted by the wind blow.
One day while in the garden, I saw a small tornado forming, growing and sliding through the walkway - I had never seen that before !
Since then, I planted some trees to break the wind blow.