Lesbians

If you preempt it by saying that they have the wrong idea, then they really will have the wrong idea. Maybe you ought to not bring friends into it. Or mention that your friends have noticed you finding excuses to hang out with her and that you thought you were being subtle, but apparently you're an open book. The thing is that if your friends and her friends have both noticed, she's probably also noticed and is waiting for you to say or do something. Otherwise she'd be making excuses not to hang out with you. (Unless she's oblivious to other people's affection like because of autism or something)

I'm of course not familiar with your communication dynamics with your friends, but your message feels like you are gently saying you're not interested. Saying you kinda like spending time with someone doesn't feel like your heart is into a 'more than friends' relationship. Also, saying you're spending time with someone because you don't want them to be abandoned is very different than honestly sharing that spending time with them makes you feel happy and you very much enjoy their company.

I'd recommend replacing that last paragraph with "So anyway, wanna find out if they're right?"

The classic "tsundere"