Are you suggesting that you think your Auntie may be dining out on Axminster? Holidaying on the Isle Of Lesbos?
If so, you need to be aware just how fragile and vulnerable she may be feeling right now. Tell her it's OK and that you love her no matter what her sexual orientations are. She's FAMILY. Tell her you're not going to be judgemental and turn your back on her. In fact, you see this as a perfect opportunity to establish a new, closer bond, an opportunity to become more involved in each other's lives. Tell her that far from holding it against her, you're so 'OK' with it that you'll even join in and munch some of that punani yourself - auntie's suchi bar is open and you're up for snacking big stylee.
Get in there and 'roll yer own' sunshine.... if they get too much to handle, just call in Uncle Johnny - hot meat on tap - always happy to help
Hope this allays your anxieties