This was the same situation I encountered and reported last week ( 01 March). No help to date from Virgin.
However lack of data connection is saving me money as I am forced to go to an area where there is wifi. Virgin are losing revenue but they don't seem to care.
Another complaint: Virgin is one of the few providers that does not consider that Switzerland is part of Europe. therefore if you use a swiss signal you will be charged for data, messaging and call receipts.
I am really sorry you've also been experiencing difficulties with roaming. Have you managed to get in touch with our team since your post? If not please pop back on here and we can look into this for you.