Here my advice
i see nothing wrong with a guy watching porno its just something they do unless it takes over their life then I wouldn't worry that didnt bother me but lying and decieving you did bother me.....
I think you need to leave him, you can still stay friends and have him in the childs life / you can stay with him and look around for other fish in the sea just because its his sperm doesnt mean that someone else cant be the dad and I know a few odd guys who would love to be a dad.
When you preggo you dont need the added stress trust me, if your worried because you dont know how you will do it then I can help you there they're so many resources available to you its insane you can get your own appt and ei/welfare plus other little benefits...
Let me know if you want to do it I think your bf is just doing it with you and I think you can do better your pretty and seem really nice I dont know who wouldnt take a leap into good luck!!
Jess