advice about husband

My husband has this female coworker that bothers me. 
•My first impression of her wasn't good because she was leaning into my husband whispering something when I came to his work unannounced. In his personal bubble is not ok! 
•They work at Starbucks and my husband always comes home with a drink for me. She's been writing other women's names on my drinks and his too. Like wtf?
•I've seen texts between them that were way too flirtatious. Mostly on her part but I shut that down real quick. I had to remind my husband that if he wants to get into management that this could hurt him so he keeps the texting strictly business now.
•she's constantly calling him from work for help because she's a new shift. She tries to face time him too. I'm talking about 4 missed calls in an hour and maybe 3 missed facetimes. He's good to tell me about those because he knows I'll see it on the bill. Once she was bugging him while he was at the gym about work.
•she's asked my husband if I liked her because when we were finally introduced, that I had a mean face. And then proceeded to ask if I knew I had a resting bitch face.
•once they followed each other on IG I blocked her and she asked him about it the next day, so he felt pressured to lie and add her back
My husband is constantly reassuring me that she is married and he just wants all of his coworkers to like him. But we have had numerous talks about my feelings about her.  Basically I got on his ig and unfollowed her. But she's still following him, I don't see the need for him to follow her. I happen to check on that and saw he sent another request. I'm furious. He's obviously not respecting my uneasy feelings and doesn't care. I literally don't know what to say or do. I've been 100% clear about my feelings. I feel stabbed in the back. Can someone give me advice?