Is it right to delete the girl who rejected you?

ok,here is my story.at the beginning of this year,i met a girl in my firm,and suddenly had a crush on her.we were all new members to this firm so i had a chance to get her cellphone number.we had a little chat for the next six months,i didn't say i like her immediately because i didn't want to be in such a rush.in September,finally i asked her for a dinner,she rejected.and in October,i asked again,and again it was a rejection.
last month,i got a third rejection,so i thought i should give up the whole thing.but this time after she said "no",she asked me why i was keeping invite her.actually i was a little surprised(or maybe annoyed) at her question.i mean it can't be more obvious, i told her "because i fell i have a crush on you" .i omit the question "can't you see that??? "
as every girl who rejected me she said we could be friend.
i was a little sad because i waited a whole year,and that was also a relief because finally i got an answer.
and after that she never reply to my messages,i just sent three.
the job was very boring so i quited it this month,and these years i kept all the girls cellphone number,who rejected me,i never connected them again.
i think it is hard for two strangers to build up a relationship,though the relationship collapsed soon after.
should delete those numbers?