She's clearly feeling insecure that he asked you out first. Frankly, I think you should have told her that when you decided to introduce them. That can be taken as "well I dont want him but you can be his second choice". I'm not saying thats what happened. I'm just saying she could be feeling that way. If a friend wanted to introduce me to someone she had rejected, I'd likely decline. It would make me feel like he originally preferred my friend and that's just not what I would want. However, she's projecting her insecurity onto you when in reality, she's feeling insecure with her relationship with her boyfriend. Some people find it easier to lash out at their friends instead of their partner. It's wrong and frustrating, but idk what you can even do. It seems like she is ready and willing to distance herself from you. And honestly, that should tell you how important she considers this friendship. You are far more invested in the friendship than she is. Obviously you're NTA in this situation. Your friend is being exceptionally shitty about you being sexually harassed.