<human>: The title is pretty much self-explanatory, but I'll delve into the story now for anyone interested.

So I'm a 25 M, with a brother of 22 and what happened is connected to a girl, but not the usual feud over who'll get her. We both liked her, that part is true. And that's exactly the reason why I approached him and wanted to clear things out. You see, being the older brother I tried to (and probably failed sometimes) help him get along with girls, study, whatever. So from my part, if he had told me that he wants the girl, I'd back off. Hell, I'd even help him.

Instead, what happened was that he was leaving some nights and didn't come back until the morning. Since he was not with any of his friends, it was pretty obvious that he's hiding something from me, and I rightly assumed he was seeing this girl. So as I said, I approached him in hopes of straightening things up. And here comes the part that really upsets me. When I asked him specifically if he spent the night with that particular girl, he looked me dead in the eye and said a very firm and convincing no. And let me stress out that I intentionally made eye contact and held his gaze.

I think Friedrich Nietzsche put it beautifully: "I'm not upset that you lied to me - I'm upset that from now on I can't believe you."

Now to have the complete story, afterwards I learned that by the time I approached my brother, he was already dating the girl and that she asked him to be quiet about it. I can understand that. However, I can't and never will understand how my brother can lie so blatantly about something so trivial (I just asked him if he was with the girl, not anything more specific) and not feel any kind of regret. Even after, he still doesn't realize what he's done.

And there are a lot of friends that say to me I should just let it go, and that I'm creating problems where there are none, etc... But I truly cannot even look at him without getting sad, as I feel betrayed. And the sadness very often escalates to anger. There. Feels good to let it out.

Could you distill the essence of the text into 1-3 sentences?
<bot>: My brother lied to me in a way it makes me feel like I've been betrayed and stabbed by someone I hold really dear.