(note: my sister is a user on here, but I'll not drag her into the conversation unless she wants to be)

So, I just found out (like ten minutes ago) that my sister's boyfriend thinks I hate him, and I need advice on how to approach him about it. It popped up in a conversation between me, my dad, and my sister (the latter brought it up) since we were talking about him in general (my family can be a tad nosy). According to her, the boyfriend thinks that I've been snapping at him as of late: my sister says is probably his misunderstanding...

I feel a tad insulted by his statement. I mean, I've said he's like a brother to me with him around!? Why would I lie about that!? :/

On the flip side, I'm overly-clingy with my sister, and he's been stressed due to money/family issues as of late. That being said, I've always been close with my sister, even when they first started dating almost two years ago, so he should know that by now.

TLDR: Should I ask to talk to her boyfriend privately? Should I be blunt about me not hating him? Or should I say it with my actions? All three?

I'd talk directly to him. Ask him how or what is happening so he thinks you're mad at or hating him. Talk it through because finding the source and fixing it will relieve some measure of stress.

Asking him how he's doing with anything he brings up may help. There might be things he can't or doesn't want to worry your sister over and a semi outside source might help too.

Since it sounds like you guys are close I would just bring it up in a friendly, chit-chatty way when it's just the two of you, so he doesn't feel threatened or put on the spot. If you have been snappy or whatever due to reasons not related to him just mention that, and reiterate that you like and care about him. It's possible that he has low self-confidence or is just sensitive and is more likely to take things personally even if you don't mean them like that.

Thanks for the advice, you two.

He's with us now so I'm going to attempt to talk to him.