OK. Let's try to get a few facts injected into this, so people learn a few things about US carrier operations.
First of all, there is little in terms of difference between the "cushy" deployments and "major combat operations". At most, you will have a slightly increased tempo of launches and recoveries, but on a carrier, once you arrive at your operational area, peace or wartime, you go into continuous cyclic ops (launch- recover - prep - launch -etc. etc.). While this is going on - and pay attention here, this is important: nobody other than flyers and flight deck crew are allowed on deck, which means that for the roughly 4,000 or so sailors that are not in that group, you have just spent 240 days inside four steel walls, never getting to see the sun, the sky or the sea, breathing recycled air, with no place to go to get away from anything or anyone.
And that's the second thing: On a carrier, no matter where you go or what you want to do, there will be other people around and you likely will have to line up and wait your turn (anyone remembers the Top Gun scene at the end with Maverick, alone, overlooking the sea from the flat at the stern of the ship and "letting go" of Goose? Well that ain't happening: you'd have a hundred people there).
So, for 240 some days, your life has been: 12 hours a day doing the exact same job (US sailors are trained to do one job - theirs and not a variety of jobs, like we do in Canada) every day, without a break, then line up. Line up to get each of your three (sometimes four) meals, line up to buy something at the exchange (if anything is left after over 180 days- if they can't get a full resupply of food, exchange stores aren't on the list of resupply either - which may mean, I am speculating here, that they may have run out of cigarettes for the smokers. Then line up to take a shower, then line up to play on the video games machines or the gym machines, then line up to... you get the gist. Then you get extra work cleaning around your section and, finally, you get five or six hours of sleep, in your cubbyhole about the size of a coffin, where the only thing separating you from the others in the mess deck is a curtain. Remember, all the while never having fresh air or seeing outside the four walls. We don't even impose such a regimen on prisoners.
And who exactly is going through this? Young kids. On any given deployment of a US carrier, anywhere between a quarter and a third of the crew (1500 to 2000 sailors) are on their first or second such deployment, barely out of basic and first trade qualification. They are 18, 19, 20 years old, first time away from home. The USN is not a long service professional's navy as we are used to have in Canada. Most of their crew are in for a five year term with a very limited number of them signing for more at the end of their contract (so much so that they give "prizes" to ships that achieve a certain percentage of re-enlistments).
So, no, it's not like Afghanistan.
This is what happens in such an environment: 3 months in: the practical joker guy is beginning to get on your nerve, 4 1/2 month in: you confront him and tell him to knock it off or else, 6 months in and over: you punch him in the face and are brought in front of the summary court by the marines. Repeat that with thousands of sailors and you can see that, on a very long deployment without a break, things can go South very easily.
Even on submarines (except the boomers - but they are limited to 3 months patrols) we go to the surface from time to time and make sure that everybody gets a chance to come up an have a breath of fresh air and see the sky.