Pictures

You really shouldn't be following people who post almost-porn kinda provocative stuff, but if it's just like your friends posting normal pictures at the beach, then I don't see the problem. But think about it bro, what do you want out of social media, how does it agree with your general goals, etc.? Generally we set our own goals and terms here regarding self-improvement, but that requires you to be very honest about what's helping or hindering.

 

I don't do Instagram, but where are you looking on Facebook? No, I do not want to know! But I am puzzled because I have never seen anything like that on Facebook! Seriously, you have to ask yourself what sort of friends you have dude!

 

Are you trying to shield yourself from the realities of the sexually charged media/world that is prevalent today or are you trying to make yourself strong enough to have the willpower to not PMO and seek out porn on purpose. Do you see the difference?
The real cure would be make yourself stronger by changing how you think and act while working on making yourself a healthier person. It's fine to try and avoid the things that may trigger you, but with all the sexual stimulation that is out there today, you better work on changing how you react to a trigger when you see one.
I think with time you will be less stimulated when you see a soft-porn trigger. Your brain will start to become "normal" and you won't be in a constant state of agitated sexual arousal because you will now be seeking out healthier options to occupy your time.