Sorry to hear this. I hope that you both soon recover.
Just because the driver has accepted her fault doesn't mean that her insurers will. Keep copious records of everything from the difficulties that you both have because of the injuries including pain, loss of mobility, working issues, ongoing issues such as headaches, dizziness, back pain, cricked necks, etc., etc. ,etc., as well as impacts on your finances and personal lives.
Don't let them downplay the severity of the incident and it's consequences.
And, all losses relating to the tandem, your cycling kit, need to get taxis, etc., etc., etc.
We have a terrible habit of downplaying the affect these things have on our lives.