Long term relationship starting to go south, jealousy and self esteem issues lie within.

Well I have made a right mess of things, these relationship question can be so broad and really dependent one ones lifes experiences and upbringing. Therefore I have tried to include as much information as possible.

I have been seeing my girlfriend since I was 21 years of age, I am now 26 going on 27 and we have had a few ups and downs but in total we have ALWAYS been faithful and have only been apart for a few months following ridiculous fights over our insecurities. My girlfriend is 30 going on 31 if that makes a difference.

We are both very inexperienced in adult relationships, this being both our first relationship.

Now at the beginning we both kinda masked our insecurities from each other and therefore I said a few things about other girls we might have seen in public, keep in mind I was 21 and had been hanging around young savages and was acting in there image as I had seen them have success in the past. My girlfriend is very attractive but has very low self esteem (mosty due to what I believe as a lack of male attention) and chooses not to dress in revealing clothes as she has so many issues with her body. Issues I can't understand but accept and try to support her. The thing is I have been way to honest with views on other girls, since here in Australia most girls dress like "sluts" in very revealing I have admitted to finding a few girls attractive in the past. She asks ridiculous questions about dolled up girls on TV such as "do you think they are more attractive then me." What a loaded question and based on my admissions in the past she knows that I probably do. She always insists that I am the most attractive man she knows which I know is bullshit. She used to admit in the beginning to men being attractive but now she doesn't find anything attractive it seems, like she wants to believe she is perfect. Now we both don't like to admit if someone is attractive however if she pushes and prods enough I will tell her.

She claims I am the one who is obsessed with appearance but I can't help and feel it is the other way around. I have been so good in recent years that I have trained myself not even to look/notice attractive girls whether I am in her prescence or not. **** really hit the fan yesterday when we were eating lunch at a cafe. An attractive girl walked in dressed in tight leggings showing a decent amount of her figure, I hadn't even noticed her but my girlfriend had to point her out saying "I bet you find her more attractive then me". I didn't say anything and tried to move on but I could tell a huge fight was coming. Now this girl was very attractive but in reality even if she was better looking then my girlfriend I would rather my girlfriend as she is such a modest person and a quick 5 second look at someone can't change how much I love and lust for my girlfriend. I would just never go there with anyone else.

With that being said on the way home in the car she broke down, absolutely balling her eyes out. At the zebra crossing another attractive girl walked past and she was screaming "LOOK AT HER, HOW CAN I NOT FEEL LIKE **** WHEN PEOPLE YOU FIND BETTER THEN ME ARE EVERYWHERE." I dont know how to handle these situations and sometimes get angry and defensive which only seems to make things worse.

I really don't know what to do, I have said so much in the past I can't go back on how I feel about girls and its not like there are heaps of attractive modestly dressed girls getting around so I could say to my girlfriend "see, I find her attractive and she isn't dressed scantily."

Seems like such a childish issue to be having considering we are both middle aged now but I really want to be with her but she keeps pushing me away.

Help please!