You might want to hold off requesting such a transfer until Virgin Media have resolved this issue? You'd basically have no access to your online account or be able to log into apps such as the TV Control app if effected by this. You'd also be unable to access any new Virgin email associated with the new account. It should also be noted that any old email accounts and boxes associated with the old account will not be automatically transferred over to the new account and will be permanently deleted 90 days after the new account is activated. You can however request that the pimary email accont/address be transferred to the new Virgin Media account, but such a transfer cannot be carried out until you've actually registered a new account online using a different email address as the username.
There's a £20 fee charged for this and they'll run a credit check on your girlfriend if she is the one taking responsibility for the account. You are also automatilly tied into a new 12 month contract.