F23 - Cheating of my bf since the beginning

So I'm in an "exclusive" relationship with my bf since 1 year now. But from the start to know I've been cheating on him with my best friend. He thinks I'm going to the gym every Monday and Thursday but the truth is that I go to my best friend home to get fucked ! You can say I'm a whore idgas I love his cock. On a scale of 1 to 10, my bf sex is 2 and my bff sex is 10. I don't wanna break up with him because I truly love him but I can't get over my best friend dick. He is the one who took my v card, in highschool we fucked in the toilets every week, we started and still doing exhibition together. He is my sextoy and I'm his aswell. What's your honest opinion about it ?