What's happened to our relationship? Are we going to break up soon?

I've been with my boyfriend for almost 3 years. For the first like year and a half, everything was great. We never fought, I was so infatuated with him, and it felt like a fairy tale. But after that we started having small arguments every now and then and it just kept building up. Since the start of this year, we have had a million arguments, some big ones and some HUGE ones. When we're together, it's not the same as how we used to be when we completely adored each other. Now he always seems annoyed and irritated at me and I act the same way back. This sounds cliche but there's like no "magic" anymore. I used to think of him and want to cry from happiness but now I just think of how annoying he is sometimes. I love him so much and don't want to break up with him. But I'm scared he might break up with me because it doesn't feel like we love each other, it feels like we're constantly irritated at each other. :(