The dog is last seen alone in the boat, but it is very much alive. Although it isn't mentioned again the dog was most likely rescued. It's doubtful they'd make a point to show it alive if it was going to die.
The reason it isn't mentioned is likely because there's no reason to. In general the dog is only mentioned a couple times.
No, but there's a short scene where a drunk man acts in an agressive way and his family looks startled and scared. He doesn't hit them, and other than that he doesn't show any signs of being violent, but it might be triggering for some people
In one scene about a third of the way in a character appears to take pills and snort a white powder. It’s not crystal clear on screen and doesn’t last long but is there nonetheless
Yes and no. Not in the traditional sense no, but there's a scene where one of the characters clears a dinner table threatingly whilst in an argument which can be startling
1:08 - 1:13. A man with light curly hair tips a beer back, then leans over and v*. No sound. Close your eyes after you see the two women fall with a case of beer, laughing, then wait 15-20 seconds. Nothing substantive takes place during this time.
The ending is bitter-sweet. One of the four main characters is dead, but the three remaining learn to embrace life, and many of their earlier conflicts are resolved.
The reason it isn't mentioned is likely because there's no reason to. In general the dog is only mentioned a couple times.