Help! Cheated on my distant BF, what should I do?

I'm a college student in Beijing, China. I have been in a serious relationship with my BF for about 4 years. I really love him and want to spend the rest of my life with him. However, he studies in my hometown, which is 1500 km away. We only meet at holidays, and almost spend most of the holidays with each other. This semester, I felt so horny that I talked with other guys in Blued (tinder in China), then he gave me a blowjob in the toilet at school. After that, I felt so bad and didn't log in the Blued for about one month. Recently, one guy in the Blued offered me blowjob. I agreed. But it turned out that I fucked that guy in ass. I felt so sorry for my BF now, but I think can't resist the impulse to get another blowjob from others. And he is going to study abroad for about 2 years. You know, guys always get horny every several days. What should I do? I do not want to break up with him.