Would YOU do this to your best friend?

Well, there’s this boy named James and only my best friend Katie knows I have had the HUGEST crush on him for about two years now. He goes to my church and boys and girls aren’t suppose to talk to eachother at church so I never really got the chance to talk to him. Then one night Katie calls me up and says “OMG guess what! I got Jame’s number for you, this is perfect I can become his buddy and hook you two up!!!”. Ofcourse I was bouncing off the walls. Then she says “I have to give it to you later cause am with my friend Lindsay.” So two days later she calls me gushing about how awsome James is and she was reading every single text message they sent and telling me everything they talked about on the phone until 4 in the morning. They were totally flirting! So basically she told me she was going to hook me and him up, she all of a sudden decides to want him when I’ve ALWAYS liked him, he likes her andd shes rubbing it in my face!! sigh I don’t know what to do. Everytime she talks about him my heart sinks. I just can’t believe she would do that to me. I told her how I felt about it, I said it upset me and she acted like she was sorry and was going to stop talking to him. Then she starting ignoring me and I just found out they are basically girlfriend and boyfriend now. I just got off the phone with her and she told me EVERY detail about them holding hands, kissing, ect. Its truely killing me. Would you do that to your friend? What should I do or tell her?