Absolutely true. I worked in Parliament at the time and it was common knowledge.
They got together 'later' in life but the knew each other from childhood. Both were Vaudeville performers and were pushed on stage as soon as they could walk.
I quite often saw PR around Westminster as she stayed with BB in her apartments, although they were both very discreet. It was a bit of a shock to teenage me, not because they were lesbians but because it was Hyacinth Bucket and they were sooooooo old!!! (Actually probably not any older than I am now!)
After I stopped working there I was no longer privy to gossip. Parliamentary workers are unbelievably discreet when it comes to the secret lives of MPs, no bugger would tell me anything! I really hope they stayed together, they were both very lovely and deserved to be happy.