There is a difference between thinking and lusting. Everyone knows about sex- they think about it because it is a fact, and internalize it into a thought, but where are your thoughts going?If you are thinking about sex all of the time because it arouses you- then think about whether or not this aligns with the Bible. Ask God to show you what He thinks. If you are thinking about sex because you're not SUPPOSED to think about sex... then maybe you can try "de-vilifying" sex. Because sex is sex just like laughing is laughing. Are we supposed to laugh all of the time? Are we supposed to have sex all of the time? Are we supposed to think about jokes all of the time? Are we supposed to think about sex all of the time? God has designed specific experiences in life for specific times, reasons. (I am not saying to try and think about sex in a sexual manner, as in lusting over it, while at the same time trying to convince yourself that this is okay... that is not what I am saying.)But, I mean. We learn about sex in health class. Kids naturally ask where they come from. And my parents slept in the same bed for over 35 years... it's not like you can avoid it altogether!Seriously, just to think about sex from a non-sinful standpoint... it's just that. And then it can pass away and you can move on. But to say that you are not allowed at all to think about it.... that's up for you to decide but it's a part of life, so it can be talked about/thought about. But there is a point where it can move beyond just thinking to becoming something that distracts you from God.Hmmm.. maybe this isn't clear. So, I will speak out of personal experience because that works for me the best. I don't think about sex as much as before because it's just sex- I know that if I put my mind to it I could lust over- I used to do it all of the time. Images still pop into my head- I mean it's all around us in our culture and what not... or I see a picture on the internet, and it can suck me in... then I start really thinking about. But while I am doing this, I know that it's not what I should be doing because my mind has moved off-center from God and onto another person... so I have to move it back- and I have to do it with God's help too. I ask Him for help, which is something He really want to do!But, when I was in high school (I am in college now), half the time I thought about sex because I wasn't supposed to, and every time I did I felt horrible about myself. And this really was the devil/a demon using this idea that I was "dirtier" than other people because I thought about sex and I wasn't supposed to. It was a big cycle of guilt. Even if it was a flash of an image in my head, and I was even lusting over it... I still felt really bad... I had to give it up to God and I had to take the power that He gives us all- that is the power to be FREE of sin in Christ- and claim it as my own. And I have to ask God to continually renew my faith and help me stay close to His wants and to Him so that I can be at my best to steer clear of things that would distract me from Him.But, don't feel condemned about it or ashamed- you might feel convicted, which means that God is telling you that this isn't what He wants for you, but don't feel condemned, like it makes you worse person than anybody else (I used to feel like I was dirtier than most people- because I was a girl and it was more wrong for because I was thinking about sex than a boy- this is very flawed and human thinking... so don't fall into it.)Just tell God your worries, and give them up to Him. If you feel like you need to confess to Him, then do that too. God is not going to tell you that you are a bad person but He might let you know about something you are doing that He doesn't want you to do, because He knows how people think. Instead, He is going to listen to you because you want to please Him. This is what He wants, after all.But it's all for our own good, do you see? God loves us so much that He wants to protect us- He doesn't want us to get hurt. And He knows that His plans are best and that if we follow them, our lives will be filled with a greater, sweeter and totally better joy than if we don't. All Praise be to God.