I have a really complicated love story i need advice on, it's long but i need help.?

me and my best-friend ariel have been friends since fifth grade, and ever since i've had a huge thing for her. she never seemed interested, and so i wouldn't try, being as i didn't want to ruin what we had. i then got a girlfriend who i went on and off with for 3 years, i liked her in 3rd grade and it never really wore off. during these three years when i wasn't with this girl, i asked ariel out, she said no, and after that i must have asked her 4 more times and she answered no. i felt like a total idiot, but i couldn't get over her. a while went by and i was on my way to virginia when i got a text from ariel saying she did like me alot, i was so happy and i couldn't wait to be with her, then 3 days later she told me to forget it. i was crushed, and for some reason she wouldnt talk to me. a couple months later i was talking to another girl... i liked her but just a little, and ive always been kind of lonely seeing as girls rarely seem to like me. then i found out from ariels frien that ariel said she loved me, her friend showed me all her text messages and i was really confused. so i told ariel i was sorry, and that i loved her so much, but how in the world could i tell the other girl " o hey the love of my life just said she loves me back...so yeah we cant be together" i mean it sounds easy but it isn't. so she told me back that shes always loved me.. this hurt me so bad, and after that we didnt talk for 2 months, after that we started talking again and everything was okay, now comes my problem, i asked her out, and she told me straight to my face, she only liked me when i was with other girls... and that i didn't get at all. i mean i understand the concept of jealousy and all, but how could she only like me when im with other girls, but get mad at me when i'm with other girls, then i brake up with the girl to be with ariel, and she says no! shes so confusing so i finally cracked and yelled at her because one day she was being a ***** to me, and i said she was a waste of my time... which i know was horrible to say, but i waited 4 years for her and all she ever did was screw me and make it my fault. i still love her more than anything, and she told me she loved me, but after what i said she won't talk to me. please give me advice on what to do, and if you're going to say something mean about ariel, please don't comment because i love her, and it will just hurt me more. and sorry this was so long :(