Avatar: Am I the only one that feels that the "sex" scene is too much for young children ?

Ok, I know that sometimes we, parents, "over-think" things and we assume that children see things in the same manner that we do. We also want to "shield" them from all the negativity and bad influences in the world.  However, I am also aware that children, no matter how hard parents try to keep them "safe", are exposed to certain things at an early age, things that are not appropriate for their age. I know because I have a five year old who strikes up conversations about things that I never spoke of in his presence that I believe are not age appropriate. The source is usually a classmate or a conversation he overheard elsewhere.
Now, yesterday my family and I sat down to watch the movie Avatar for the second time. We ordered it OnDemand. The first time we all saw the movie together was in a movie theater. So yesterday, I once again felt uncomfortable during the sex scene, uncomfortable because my children were watching. Now, for those of you that have not seen the movie, it is not a sex scene that shows graphic images. However, the insinuation is present in the short scene. It is not an ongoing sex scene but it is rather short. Granted, the movie is rated PG-13 but even so, I do not think that it is appropriate for a child (13-14), even accompanied by his or her parent who will be sure to give proper explanations of what they are seeing, to be watching... call me a prude or crazy. I did everything I could to distract my children during the short "sex" scene. My husband thinks I am nuts and that I am overreacting.
Then, I thought about this: What if I am "over-thinking" the sex scene too much. What if the majority of the people think that it is appropriate to watch because the majority of children do not make anything of it ? Perhaps the majority of children see it with pure eyes and see only two people who love each other (even if one is an alien and the other is a human spirit/mind in an alien body).
My understanding is that the makers of Avatar actually deleted a more "graphic" sex scene in order to keep the movie with a PG-13 rating. However, the full sex scene will be available on DVD.  Without giving much away, I will say that it is different from "human" sex. However, the intimacy seems to be very present in the movie. The "sex" scene is not the only thing in the movie that makes me cringe. The language is also a problem.  I am sure that many children have seen the movie. How then do parents pick and choose ? How do parents make the decisions about what their child can or cannot watch ? Do parents feel that it is appropriate to watch movies with curse words because the language in the home is far worse than in the movie ?

 Back to the intimacy issue. I do not think that showing love and affection in front of our children is wrong. I believe that it is actually healthy for a child to see his or her parents hugging and even giving one another a kiss.  Showing our children how beautiful love is between their parents, or amongst family members by saying "I love  you" and hugging one another is wonderful.  Yet, somewhere along the line it gets perversed. Or is it that I feel that sharing something so special and intimate on a sexual level between adults (regardless of how it is done) should be kept private or it loses its special quality ?  Maybe I am the one with the problem. Could my "over-thinking" be pushing my children to do things that I want to keep them from doing ? Or should I continue to do the best that I can to make sure that my children see, hear and watch what I believe is appropriate for them ? After all, they are MY children and I am responsible for them.
I guess it is up to each parent to use his or her best judgment to ensure that he or she raises healthy and happy children that will eventually have to function on their own in society.

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