He should handle it right?

There's this girl that my husband works with that is always liking his posts on Instagram and Facebook literally seconds after they get posted like shes watching his page. Well there have been a couple times where shes has sent him something through messenger at like 10 PM and most recently 2 am (a meme about Netflix and Chill) and I told my husband he needs to tell her to stop because she's being disrespectful to our relationship. Shes also texted outside of work and recently it was way past work hours and not work related. She has a boyfriend so you would think she would get it. My husband showed me both messages so I know he has no interest in her and hes always been super open with me, but I think he needs to tell her to stop. Am I being crazy or should he handle it?

Update**

Thank you for your input. I honestly wanted to make sure I wasnt being unrealistic. As far as getting/having proof she likes him, its honestly my gut intuition. I've been to visit him at work and when I get there she's either talking with him or watching us the entire time I'm there. As a woman in a relationship I would never send a coworker a message at 2 am about Netflix and chill in my opinion shes hinting at something. And her previous texts have always been non work related. They've always been about personal things or her saying a customer at work is making her uncomfortable like he should take care of it. These are the things that give me the feeling she wants more from him and why I think he needs to say look no problem being friends but there are boundaries and you're crossing them.