Everyone has these fantasies. Some people more, some people less. We are human beings and not angels. Hakadosh Baruch Hu created the world in such a way that men and women are attracted to one another and, because of this, people get married, have children and populate the Earth. If it bothers you that you struggle with these thoughts, that is already something to be proud of. If we get down on ourselves about fantasies, we become sad, and the sadness brings even more fantasies, and this becomes a vicious cycle that is difficult to break away from. However, the moment we start to look at ourselves in a positive light, we will see that the fantasies will come much less often.
The Ba’al Hatanya (Chapter 27, abridged) writes about those who subdue these bad thoughts:
The Zohar (p.128) extols the great satisfaction before Hashem when the sitra achra (the other side) is subdued here below. For then the glory of Hakadosh Baruch Hu rises above all, even more than is possible through any praise, and this ascent is greater than all else.
Therefore, no person should feel depressed, even should he be engaged all his days in this conflict, for perhaps because of this he was created, and this is his service -- to constantly subjugate the sitra achra.
They tell a story of a Ba'al Teshuvah who once came to one of the Chassidic Masters with a question. Having done Teshuvah for his past evil ways, he found that he was still plagued by bad thoughts and fantasies. The Rebbe gave him a parable:
There was once a Jew named Moshkeh who owned an inn where he used to sell wine and spirits to the gentile peasants of the area. After a while, he became disgusted in dealing with the drunken gentiles and decided to go into another line of business and he closed down the bar. That evening, there was a banging on the door. "Moshkeh, Moshkeh, open up! We want some wine and spirits!" "Sorry," Moshkeh replied, "from now on, the inn is closed." The gentiles had no choice but to leave disappointed. For days, and even weeks afterwards, Moshkeh would keep getting knocks on the door, but as the word slowly spread that the bar was closed, the knocking became less and less frequent, until the gentiles stopped coming altogether.
The same goes with these thoughts, explained the Rebbe. After doing Teshuvah, the thoughts keep trying to get in. But, if we keep the store closed and refrain from our past behaviors, the thoughts too will stop coming to us after a while.
Practically, we can control our own minds to an extent. For some people, the following technique works well: Think of a "clean" pleasurable image of a place you've been or an experience that you enjoyed. Concentrate on this image for a while with your eyes open or closed. Feel the feelings, see the picture and hear the sounds all around you. Now, every time an old image or fantasy comes up in your mind which you want to get rid of, simply replace it with this good image (see “NLP Swish technique” for more info).
Others suggest focusing on your breathing as you inhale and exhale deeply for a couple of minutes. This exercise has the power to divert our awareness from our thoughts as we focus on the breathing in our body. It is also relaxing and releases the tension and pressure built up by the lust we experience through the fantasies.
One person wrote on our forum:
You can't wrestle with a pig and not get dirty. The thoughts will come - accept that. It doesn't mean anything. Worrying about them or doing something with the express purpose of getting rid of them just won't work - you're wrestling with a pig. It’s like trying not to think about a green elephant, that will only make you think of a green elephant more. When the thoughts come, try to just acknowledge that they popped into your head, wish them a friendly 'shalom aleichem!' and then move on to try and do something else.
In the Chassidic literature (see Likutei Moharon 27:8) it is brought down that getting bad thoughts and fantasies is actually a zechus. They give a person the opportunity for teshuva and proper tikkun for past aveiros. So many people get down when they get these thoughts and feel bad about themselves. But these thoughts are there in order for a person to chase them away and merit true teshuva. The thoughts come to a person so that they should uplift them. Kabalistically, the thoughts have somewhat of a life of their own and actually WANT to be uplifted! So just realize that your current challenges are intended for you to attain teshuvah shleima. Knowing this can prevent unnecessary hindrances and should invigorate us for continued growth.
Teffilah is a very powerful tool in this struggle as well. When feeling under attack by lust, say: "Please Hashem, save me from lust! I want to love You, not flesh and blood". Or say; “Ribono Shel Olam, I know that it is my fault that I have these thoughts. I don't want them. Help me to distract myself to something else and leave them be.” Even short “foxhole” type prayers can work wonders like: “Hashem, Help me. I can’t do this alone.”
See our website www.guardyoureye.org and sign up to the chizuk e-mail lists, to learn many more great techniques on dealing with persistent fantasies and lustful thoughts.