If you can fix it yourself I would, as the last thing you want is a claim on your policy and a big excess.
And, even if in the end, it comes from her insurance, it will be logged on yours as a claim! I hate this world!
Happened to me, my next door neighbour was trying to park up, and apparently 'pressed the gas instead of brake!' and went right in my bonnet.
Being dead funny about it, I had to go through mine, and when it came to renew, my premium went up! Even though in the end, her insurance paid out!