Help what should I do!!!

My fiance and I have been together for 4 years, for about the last year or so we have had a huge decrease in our sex life, and intimacy. He just doesn't seem interested anymore, and he swears its not true and it is not me, but what else could it be? I have tried just about everything, I have talked to him about it, cried about it, (to him), and now it is just a fight. I stopped putting so much pressure on the whole situation, and NOTHING changes. He rarely wants to have sex, maybe once a week, and only usually if he has had a few beers. What do I do??? I am 100% sure he is not cheating on me, so what could the problem be? i think he just isn't physically attracted to me anymore, and not sure if this is his way of acting because he doesn't want to be with me truly. Or if I am just being insecure. He says that he is attracted to me, loves me, and wants to be with me, so I don't know what to think. Even the simple things he used to do, the little things, the hugs, kisses, etc. have significantly decreased. PLEASE HELP?????????? Could it just be our relationship is dying? We now fight alot because of this, and other things, I am only 21 years old, and he is 27 years old, and only 4 years into our relationship, this stuff is not supposed to happen yet! We have two children and he is a good dad so its sort of like i don't want it to end badly because of them. He can be really horrible and selfish and call me names and surly if you love someone you shouldnt say awful things even if it is just cause you are grumpy plus never used to be like this. I feel he dn't apprechiate the things i do anymore he dont treat me or take me out i feel like he is just a lodger most of the time. how can i bring the spark back have spoke to him a 1000 times but i am just wasting my breath. He dont even care how much this is killing me inside feeling unwanted and unloved otherwise he'd do something about it.

Here is a possible answer for you, its like in the beginning of a relationship everything is perfect but as you get comfortable it slips away the romance, and the intimacy, he might not see a problem with it once a week. The age difference believe it or not is also a big deal he might not have the energy anymore men also start losing testosterone to, you are probably looking to much into it.

I'm sorry if this sounds mean because that's not what I'm aiming for,this lack of interest had nothing very little to do with testosterone.Let's be realistic......you are a 21 year old who has 2 children for a guy you have been with for 4years and has not married you...let me give him the benefit of the doubt "yet".And now he is seems distant,uninterested.Do not forget that time is very important,you should get to know a guy very well before you relax,and then when you both are certain and ready you can get married and have kids.Never the other way round,but that's what this is about.Got a quiet place alone,you need a friend because every decision you make now will affect you kids and I know you love them do have to do this right.When your in a quiet place alone,go on your knees and bare your heart to Jesus,he loves you he never gets tired of listening.ask him to forgive you all your Sins and ask him to guide you on what exactly you should do,ask him to teach to recognize his voice,he always has the best answers.He loves you and he will always answer when you call so don't doubt.Thank him for answering you when you do this and before you do this make up your mind to trust him.In the mean time don't trouble your fiancé,sex isn't everything,it can't add a moment to your life so don't trouble yourself,take the time to know your kids more and o something productive maybe learn how to play and instrument or whatever your dreams is.Take time to pray to Jesus everyday,thanking him for all he had done for you,remember he loves you and he will always listen.If you like my advice you can get back to me on this page.Stay safe,Jenna24.