My 30yr old girlfriend sleeps in the same bed with her mum a lot, is that normal?

I'm 37 and my girlfriend is 30 we started a long distance relationship knowing she would be moving closer to my area, anyway she told me she sleeps in her bed with her mum, as there's rats in the place they were staying in so I didn't think anything of it, whenever she and her mum to off to explore areas and have hotel stays, they share the same bed for cost reasons, but since moving down south she has bought her flat, and even though they can easily set up two beds for two separate rooms, they choose to sleep in the one bed, they blame the other room being damp, when they go to her grandparents house they sleep in the same spare room bed which I guess is another convenient reason, just seems to be all the time, they both don't work but are looking to get jobs soon, I've never had a relationship like this before where the girl and mum always sleeps next to eachother,

My 30yr old girlfriend sleeps in the same bed with her mum a lot, is that normal?
Post Opinion