Perhaps you should have gotten her number; the whole "Guy chasing Girl" thing.

Next time you see her, ask her out for a coffee. Coffe shops are normally relaxed environment where you can get to know her a little better.

Don't wait for her. Go after her.

BTW, Congrats on the weight loss. That's real motivation. But avoid bringing that up too soon to her. Once you guys become a 'couple', mention it and she'll be like "awwww" and be all over you