It may sound bad for what I am about to say, but I don't want her to move on yet. Idk what's the word. Pure? Cute? Whatever it is, I think she should let herself indulge in her feelings.
She's a good girl. Non-toxic, earnest, not overblowing her one-sided feelings, not making a big deal out of it. It's such an uncommom character even irl, that I want her to be this way for a while longer.
Let her flames of love die out slowly on its own.
She didn't invite his girl but it's not so bad, she's not aiming to do anything with him, it was just for her self.
It may seem unhealthy, but is it really? Are friendships completely impossible to maintain once one catches feelings? Feelings can be left to fade over time, or you get used to it and then it's as if it's not there. I don't see the need to make someone like another person just to move on. Not everyone is desperate for love. A healthy person can go on in life without having to concern themselves with romantics endeavors until the time comes, even if it means going through one sided feelings.
Not gonna lie, out of all the relationships I've had, the subtle crushing phase is very enjoyable when it's kept healthy.
I apologize for the long comment, but I was also trying to make a point here because I knew people who send themselves to ruins because of love. Without realizing, they make the pursuit of relationships their personality, especially when they have no luck, no rizz, no aura, no redeeming qualities. Yet, instead of reflecting on their actions, they jump their one sided feeling from one to the next, rejection after rejection. They consult friends and all, but from their one sided view, you're just being fed with their delusions and you end up supporting them, ("It's okay, you'll find someone better. She doesn't deserve you"). In reality their crushing is toxic. Being friends just to pursue someone romantically, neglecting everything else just to simp for her, not getting the hints that she's uninterested, being suicidal, blaming others, antagonizing the person that rejected them, etc.
In contrast, this character's personality and approach is really relaxing. So, you go girl! Just don't hurt yourself and slowly fan out those flames.