My thoughts are keeping me from being happy in my relationship

I've struggled in relationships before for being overly protective and controlling, and I am trying to improve myself. Currently, I am pushing negative thoughts as side but there are just some that I can't seem to get rid of. I have been cheated on in a previous relationship and it has caused me to panic over stupid things. My latest issue is that I've never really been OK with the idea of my boyfriend watching porn, to me I see it no difference in watching a video of it and actually sitting in a room watching people have sex. I've been with him for 2 months and it is long distance so I can accept that its a big thing to ask him to stop. I spoke to him about it and explained how I saw it and even offered that I send him things to use as material instead of porn but he just defended porn and it has actually made my thoughts worse. I have said that I understand and to just drop it and forget I mentioned it, but I'm not OK. I really don't know what to do, whether I am just having unreasonable thoughts or if its something common. Please help me either see things in a more reasonable way or advice on how to handle the situation.

The best way to handle the situation is find someone who shares your values and doesn't have standards that grate against yours...and preferrably someone who is local to you. LDR's have a bad habit of self destructing and causing issues even after years of solid marriage. If you have an issue with porn, then you need to find someone who doesn't need it or defend their use of it. By you offering your BF alternatives to it, you are admitting there's a problem in your relationship which you don't need and you are, again, trying to control the situation in which you would have solved the issue your way if he accepted your alternative. 2 months is early days but you have 2 issues..the use of porn and the fact that your BF isn't with you locally. Not a very secure situation to be in given your past problems with relationships and hence your negative thoughts which keep on coming back, regardless of your efforts to do better. In black and white with no grey areas, you are wounded and insecure from a previous relationship and now you are in another where problems are emerging over which you really have no control, nor do you really have any right to dictate to, regardless of the distance. You either accept the other person in your life, warts and all, or you don't bother...it's that simple.