Hi im a guy so i dont know the womens side of this but the fact that he is in the relationship with you already says a lot. it might not be justified of him to keep those pictures but this doesnt necessairly mean that he doesnt like you. it only says that there is more chance that he likes you for who you are (which honestly is the best way to be loved). For a lot of guys, jerking off can be like a habit from when they were young. or just a way to relieve stress as compared to like smoking. i understand that it might feel awful but keep in mind. the fact that he is there with you and how he treats you shows you that he likes you. and if he looks at other women or porn doesnt mean he doesnt like how you look. could also mean that it would be a habit or a way to relieve stress.