Realize that such thoughts have plagued even some of the Prophet's companions.
Abu Hurayrah (Ra) reported that some of the people of the messenger of Allah came to him and said: Indeed we perceive in our minds that which every one of us considers too grave to express'. He replied, "Do you really perceive it?" They said, "Yes." He said, "That is true faith. [Muslim]
Ibn 'Abbas (Ra) narated that a man came to the Messenger and said, "O Messenger of Allah! One of us has thoughts of such a nature that he would rather be reduced to charcoal than speak about them." The Messenger (may the peace and blessings of Allah be upon him) said, "Allah is the Greatest! Allah is the Greatest! Allah is the Greatest! All praise be to Allah wh has reduced (the shaytan's) plot to whispering. [Muslim 2203]
What does this bring up for you today?