What should I do if the girl I like is in a relationship with another guy?

I am 14. I have been talking to this girl for about 2 months and we’ve become really good friends. I told her I liked her awhile ago and she responded neutrally. She has been in a relationship for about 6 months. But, her boyfriend is away ALL summer. 2 months. I really like her, but I don’t know what to do in this situation for the summer months.