It is sad Flying Handbag but if you can see them and talk to them, that will have to do for now. Instead of making yourself unhappier because you can’t hug them, make the most of their company and conversation. Hugging and personal contact are what spreads the virus.
At the risk of comparing your situation with others there are many many here who cannot even see their children, grandchildren or parents in person and may not be able to do so for months.
We are all in it together and having to make the sacrifice so as to not spread this deadly virus.
You would never forgive yourself if you caught it from a visiting family member or passed it your parents, who I assume are in the dangerous age group.
Be patient!
To think that London, or anywhere else for that matter, does not belong to any one demographic