love problem...help!

i date my girlfriend for 6 months now, but after 3 months we have been together, i always act like a kid, always get angry about the small stuff. and she always keep patient. then on valentine's day, i did it again, made she sad and she told me she doesn't have feeling with me anymore, and she start losing faith in our relationship. 3 weeks for that "no feeling relationship" with me, last night after i called her, she told me please give her 1 month for "cooling", then during the cooling time, she asks me not to date her out or call her. after 1 month, she will give me the answer about we can continue or not.

i told her i will change my attitute to her, even bad personality like jealousy etc.
but now in a month i'm not being with her, how can she see me the changing in myself?
and what else i can do during this cooling time to prove her "i've change, i'll never make u sad anymore, and i love u so much"

please...help me...
thanks before...