Oh dear I sense another porn debate coming up...
OP fantasizing / imagining about another person in the mind is NOT cheating. Finding that person and '****ing the shit out her' as you so eloquently put it IS cheating. IMO your strong aversion to porn stems more from your own insecurities than porn itself. You feel uncomfortable that he watches it and gets off on slimmer women. Would you have the same problem if he was getting off to watching fuller women with cellulite, stretch marks and jiggly bits? Porn is fantasy. That is all.
I agree your BF is being lazy. And the fact he doesn't take your needs into account also means he is selfish as pointed out by Vincenzo. Also depending on how often he watches porn and masturbates this will affect how often he wants to have sex with you. More of the former and he won't require sex with you as much.
The only thing that is going to improve your situation is communication and by you telling him how you feel. No yelling or screaming but a mature, adult conversation. If he is not willing to change then I suggest you re-evaluate if that is the type of relationship you want to be in. Remember if he truly loves you he will do everything in his power to fix this issue.
As for the porn that isn't the main issue here and you will continue to go in circles if you focus on it. By him watching it you will feel worse about yourself, you will become more aggressive and wanting sex more (as validation that he finds you attractive) and he will become more and more disinclined to have sex with you because of this, thus he will instead watch porn and filling his needs that way instead. Can you see the vicious cycle? When sex becomes a chore it is NOT enjoyable. You need to try and get him back into the place where he WANTS to have sex with you. He needs to understand this and cooperate.
Good luck.
Some people are drains and some are radiators... Keep clear of the drains and hug the radiators!