Do women like to feel protected by their boyfriends?

It just upsets me how much of a push over I am. I am 5ft 7 and my girlfriend is 1 1/2 inches taller than me. It really upsets me when people give her unwanted attention and flirtation, even when I am next to her. I mean once there were these drunkards giving her derogatory remarks, yet I just told my girlfriend to ignore. She too so much abuse due to me, and now I feel like an ****.