It was like this at my old place. Things leaked, there were sharp edges on fences, broken rails and stalls... we'd always ask her to fix things, and she always said "I'll have my husband do it tomorrow" but he never did. The last straw was when my mare came in one day with a huge cut on her forehead from a piece wire fencing that needed repair. I was so mad. It was a while before I was able to move my horses, but until I could, I did all my own repairs, and then started telling the BO about it, and how much it cost me to do. I even once told her I wanted it deducted from my board. However, she didn't get her act together, and I moved my horses to a barn we built this January.
It was so frustrating.
I'd try to explain things to her calmly, but if she doesn't understand, tell her you're going to make the repairs yourself, and as BO, she's responsible for paying the damage.