HELP... Need relationship advice!!!!?

Long story. From the top shall we. Okay so when my now fiance and i first started dating, i was still talking to my last boyfriend. And i told him that i still loved him. Bad idea. My boyfriend found and was very upset which is understandable. Ever since then he has been very insecure and thinks that i am going to go back to this guy. And since this incident i have not talked or even seen my ex, not giving my fiance any reason to think so. It has been 2 years and we are now engaged and have a 7 week old son together and he asks me every now and again if i still think about him and i am honest with him and tell him yes. But its not like i lust over him, he just pops into my head once in a while. Which i have been told by several people that its normal, he was a big part of my life and there is no way i can erase those memories. Now there is a big problem in our relatioship because ';I cant get him out of my head'; So he says. I have explained to him several times that i dont want to go back to my ex, i wanna be with him (my fiance) and i wanna marry him. But that just isnt good enough. He expects me to erase my past and my memories of my ex to make this work. We are now very close to breaking up because of this mess, and i want to know AM I AT FAULT HERE??? Is it really that wrong to have thoughts about your past. Please, i need advice as i am going crazy. Thank you! And hold the nasty comments, im already a basket case.HELP... Need relationship advice!!!!?
ItS ToO lONg :)


SoRryHELP... Need relationship advice!!!!?
its okay to be in a new relationship and love/care about an ex. It may create a problem however if you are still in love with the ex. Many reasons but one important one is that it may close you off emotionally from your current relationship.
its memories u cant forget the past. i think he is just over reacting.i know how it feels and is very common
it is normal because u cant erase the past but at the same time dnt speak of him 2 ur fiance anymore keep ur thoughts 2 urself because its tearing u guys aprt...simply say 2 ur fiance '; wat can i do 2 keep us 2getha because ur the only 1 i wanna wake up 2 everymorning ill do anything 2 prove my love 4 u .. like i sed my ex is my past an its not easy 4 me 2 get but i am focus more on my present and future with u so how can we work this out?';
Okay Darling, its not wrong to think about him... and its not easy to forget any person who was part of your life for a long time... But you shouldn't have told him about your past.. Past is past, you should have left him there itself.. See, its ruining your present... And being honest is good, but what is the use if you won't have this relationship going.. Listen girl, I am too young to advice you, I am just 19 and I don't have a baby like you, but I do have a BF.. Guys don't accept the girl's past easily.. I won't be marrying my BF even though I love him more than anything and I also know that I'll never tell my future husband about him cause I know, he'll never understand... Guys are not like girls... They can never be.. Please.. tell him, you'll forget him soon and will never talk about him.. And ask him to stop asking as well.. Just a little lie can make your life.. He is your present and future, don't let him go for that past.. past is a pest...