As MrSaffron says, nobody said that. Quite the opposite.
But you also used an unusual way of describing your Virgin service. You said FTTC, which technically it is, but no-one ever calls it that. So jsut to confirm, you do mean VM Cable? Not VM ADSL2+?
On VM Cable the only ISP you can have is VM.
You were told that for anything except Virgin Cable you would need a landline installed. You can order broadband from nearly any ISP in the country to run on that.
Because the two are on separate lines you can obviously have both services running.
O2 can supply just broadband, or a phone and broadband bundle like you have with VM. My warning was that if you took a bundle and you later wanted to move the ADSL2+ to another ISP you would need to move the rental of that new line to another company. (You wouldn't need another new line). If you get the new line from somewhare like the Post Office or BT Retail that becomes far less likely, and you can still have your O2 broadband on it.
My broadband basic info/help site - www.robertos.me.uk
My domains,website and mail hosting - Tsohost
. Internet connection -
Plusnet Value Fibre.
"Where talent is a dwarf, self-esteem is a giant."
- Jean-Antoine Petit-Senn.