So I (21f) have been with my boyfriend (27m) for a while now, we've known each other for almost three years. Lately, I've had thoughts about wanting to be single or that maybe I shouldn't be in a relationship anymore. At first, the thought would be occasional after an argument that we've had; however, recently I've had the thought for two weeks straight without any meaning behind it, and I know it's not normal when you're in a relationship. Before any of you say anything: THERE IS NO ONE ELSE. I'm emphasizing this because that's what this sub ends up being half the time.

I've asked a friend for advice, and she told me to think of why I might be unhappy and want to be single, and if it's a decision I'll be ok with, then I should do it. However, part of me still loves him, and he is someone that I could see the future with (and vice versa). At the same time, though, I can't ignore a feeling like that; it wouldn't be fair for me or him. So, AITAH here?

EDIT: He's 27, not 26. I apologize for the mistake.