Dog sleeping sometimes in my bed, sometimes off my bed.. is this bad?

I’m getting an 8 month old dog and I’m wondering if I can decide on the fly whether she sleeps in my bed or next to it in a dog bed (perhaps sometimes even a crate)

Essentially I, as a single person, think having her in bed is great

But with dating, intimacy, etc - it won’t always be the best situation and having her beside the bed on the ground would be ideal (in a dog bed)

Is it better to have a hard and fast rule of never letting her sleep in the bed? Would allowing her sometimes be bad for future habits/behavior? Or can I train her to be happy with all situations (human bed, dog bed, crate)

Thanks so much!