Please help!!!

I usually don't love girls despite being with many in my life. I'm just a nice and kind guy that want a to make life easy and enjoyable for anybody I'm dating. But I love my current girlfriend so much, never believed I will love a girl this much. I would like to marry her and I'm sure she wants to spend her life with me too. The problem here is I am not really a fan of public proposal neither does it appeal to me to kneel down and ask a girl "Will you marry me". We have argued about this issue more than we have argued about anything else since we started dating. For some reasons over this period my hard line view has soften so much and I feel I should just do it now at least to make her happy. (Off course i have a very beautiful idea of how to do it and it would supercede most she has seen on the internet). But recent event is making me reconsidering if I should do that. Why do girls see this as an ultimate proof of love and respect? Do boys do this to fan the ego of their ladies or is there a reason behind it? Why do I still have to propose when you know I have been really serious with you over a year and we have planned our lives, future together? As a matter of fact she told me this morning that if i find someone i love i would propose to the person insinuating i dont love her and it really hurt me because contrary to her view i love her so much. Please I need honest advice and opinion