Female perspective:
She's dangling the carrot to either get you to behave the way she wants you to where you will be rewarded with consolation sex to reinforce more behaviour to her liking (never ideal),
or, she is stringing you along for attention/ validation to boost her ego.
Both signs of low interest. If a girl doesn't want to put out that's one thing,
but not wanting to put out then inviting you to sleep in her bed while giving you the vibe that you should not make out with her is a demeaning power trip move that will f**k with your head.