Think Anji Greaves was trying to make a buck from the newspapers.
In fairness to Anji, she supported him after charge and visited him all the time while he was on remand prior to trial. It may have been a genuine love and she genuinely believed him innocent. Seems as well they were seeing each other in some capacity before the massacre or just after it.
Remember it was never " the bastard got caught scenario" Bamber always maintained innocence.
Naturally they parted company after he was jailed for life.