I saw a thread recently about someone who was worried that their sibling was moving too fast in a relationship and she was worried about the heartbreak it might cause.
Cue lots of posters saying smug comments (without even reading the problems the OP said) like - "We fell in love after a week. Move in after 2. We just knew."
You cannot know someone, like truly know them after one week or even one month.
I do not believe in love at first sight - I believe in lust at first sight. AIBU?