Hi
I've not heard of Satcom ever being used to call home for chats. Costs a fortune to use and you'd get in bother using it for personal use. You wouldn't want to anyway. Skype in the hotel is easy and free. You've got e mail etc.
The atmos depends on the company I suppose. Places I've been haven't been much different to the pax operators. Friendly and relaxed, just as professional. On the rare occasion you fly with someone who isn't a great character fit with yourself trips can be a bit longer mentally. If you're heavy crewed you sometimes get a few hours down back to sleep in the bunks, mooch about or watch a program/film on the iPad if you can't sleep. Anything to try and rest.
The grooms go downstairs onto the main deck in flight to check horses. They're supposed to carry bottles and tell the crew.
Long haul freight is a bit like a cross between being submarine crew/being on a supertanker and flying. You can be away loooong spells, spending hours in a cramped upper deck with fellow crew/grooms with a self service galley and some bunks. If you were suddenly taken to a freighter upper deck mid flight from a pax cabin it would seem very different in that regard. Interspersed with being parachuted into many countries and cultures, your world becomes an endless stream of meeting agents that whisk you through confusing immigration clutching gen decs at odd little airports in strange places before being transported to a hotel and then going to bed after breakfast.
The rolling jet lag with back of the clock flights can leave you mid trip all of a sudden feeling like you've been away months (when it maybe a week) and not quite knowing which planet you're on. Jet lag and tiredness is one thing that unites the crews. We all appreciate it and on the occasion when you're at a station where there maybe a few crews in the place no one is suprised if a few don't show up in the evening as arranged. Everyone's body is telling them it's different times.
Good camaraderie on layovers if a bunch of you. Sometimes though if just 2 of you for whole trip it's vital to get a bit of downtown on your own. Interesting you mention loneliness. Even if you're out socialising with crews when not asleep the job can feel very lonely on occasion. It's easy to feel detached from life. You come home and alsorts has happened whilst you've been away. No one understands, unless they've done it how knackered you are and that you just want to not go anywhere for a few days, instead potter in the garden etc. Friends outside of the industry will never understand it. They think being away 14 days is like them working 14 days in their day job and why don't you want to head out the weekend you're back, stay over at theirs and have a busy weekend? It takes careful managing of friendships and relationships.
There's many highs, and lots of lows. I don't care what I fly anymore but for me what's important is lifestyle, how well I'm paid and how I'm treated by my company.