Why do i loose my train of though?

Wow it's hard for me to explain how for the first time in my life. Normally my words come out with ease and sound pretty intellegent without me having to think much about them, but lately i've been slightly inarticulate. It's just when i look at him i loose my ability to think.I get intrigued and infatuated beyond measure. And when he talks to me it's like my mind takes a temperary vacation to cloud 9 and my mouth involontarily speeks. It's so bizarre and i don't understand why this happens to me. I've never been like this before but i've never felt like this either. I mean i've never been this exhilarated and happy before. It's astonding. But the loose of thought kills me! It makes me feel stupid like i'm incapable of holding an intellectual conversation. AND I'M NOT! It's infuriating!! But i really haven't a clue how to fix it...and i'm going insain.