We haven't seen the direwolf at all this season.
According to GoT producer-writer Bryan Cogman, there was meant to be a farewell scene between Ghost and Jon in Episode 2, but it was cut.
In Season 7, Episode 5, we finally got an in-show mention of Ghost and what the hell he's been up to. According to Sansa, he's just...sitting around and waiting for Jon to return.
Meanwhile JON IS OFF PETTING DRAGONS. My heart hurts.
So while it's understandable on an intellectual level that the show's budget limits how much we see Ghost, on an emotional level it fucking sucks. And it's incredibly unsatisfying from a character standpoint when you think about how important Ghost has always been to Jon.
Jon is the one who, when the Starks find the direwolves, sees the potential connection between them and his siblings. It's the first (but not the last) time we hear him say, "I'm not a Stark". And it's at this moment that he finds Ghost.
For a while, Jon takes Ghost everywhere – including to the Wall when he joins the Night's Watch. There, we see him use Ghost to intimidate Rast so he stops bullying Sam.
Jon also takes Ghost beyond the Wall when he makes his Night's Watch vows. It's there that Ghost finds the corpses of the two men who had left Castle Black with Benjen Stark – the corpses that turn out to be Jon's first encounter with wights.
In fact, it's Ghost who senses something is UP after they take the corpses back to Castle Black. He leads Jon to Lord Commander Mormont's chambers, where Jon finds and kills his first wight.
A pretty pivotal moment in Jon's storyline, and also the event that causes Mormont to give Jon the sword Longclaw, complete with a new wolf pommel resembling Ghost. Because, he says, "I wouldn't be standing here if it wasn't for you and your beast."
When Jon leaves Castle Black to fight alongside Robb after hearing of Ned's death in the Season 1 finale, Ghost is right there with him.
And, of course, he returns with Jon when Sam, Grenn, and Pyp convince him to honour his Night's Watch vows rather than abandoning them for his family.
When Mormont later addresses Jon about how the REAL war is with the dead, not for the Iron Throne (sound familiar?), he says, "I want you and your wolf with us when we ride out beyond the Wall.” So Ghost joins them on their mission to investigate what the hell is happening with the wildlings, wights, and White Walkers.
The next time we see Ghost on screen is in Season 2, Episode 2, where he's a lot bigger (and hence, CGI, so this is where we start seeing him less and less). Here, Ghost actually helps Sam meet Gilly.
Later, Ghost is there, just casually chilling in the background, when the Night's Watch reach the Fist of the First Men.
And he follows Jon when he joins Qhorin Halfhand in the mission to kill the wildling lookouts (i.e., how Jon later meets Ygritte). But Ghost wanders off, which, let's face it, was likely because of the limited CGI budget. It does enable this nice exchange about Jon's feelings about Ghost with Qhorin:
While Jon goes on to be captured by the wildlings, Ghost apparently makes his way back to the rest of the Night's Watch at the Fist of the First Men. The next time we see him is in Season 3, Episode 1, when he saves Sam from an attacking wight.
He follows the Night's Watch back to Craster's Keep, but refuses to go near the place. This is around the time Gilly is giving birth to her baby, and right before the mutiny against Jeor Mormont happens.
It's not until Season 4, Episode 4, that we discover that the mutineers actually captured and caged Ghost. Meanwhile, Bran and his companions are nearby, and Bran wargs into Summer and sees the caged Ghost. Summer falls into a trap, and Bran and the others head to Craster's Keep to free the direwolves and find out what's going on.
This leads to them being captured by the mutineers themselves. Bran nearly reunites with Jon when he attacks the Keep and kills the mutineers, but he leaves before Jon sees him so that he can find the Three Eyed Raven. Not before Hodor frees both Summer and Ghost, of course.
Ghost then kills Rast...
And finally reunites with Jon for the first time in two seasons – much to Jon's delight.
When Jon returns to Castle Black, Ghost is with him, and Ser Alliser Thorne orders him to lock him up.
Jon orders Sam to free Ghost when the wildlings attack Castle Black, because he needs him in the fight.
Ghost immediately gets to work taking down wildlings.
Like the hero he is.
In Season 5, Episode 1, Ghost is seen just chilling with a bone while Jon trains Olly.
Ghost stays behind at Castle Black when Jon travels to Hardhome, so he's there to help Sam save Gilly from the two Night's Watch men who attack her in Season 5, Episode 7.
Skipping ahead to Season 6, Episode 1, and Ghost's howls are the first thing we hear, as he desperately tries to get to the murdered Jon. It's his howls that alert Davos to the fact that something has gone wrong, leading him to discover and protect Jon's body.
Davos gets Edd to bring Ghost into the room with Jon's body, as they prepare for an attack by Alliser Thorne. "We need all the help we can get," Davos says. When Ghost enters the room, he mournfully sniffs Jon's hand, and lies down by his body.
The direwolf growls and is obviously keen for a fight when Thorne does come knocking at the door.
While Thorne tries to bargain with Davos, and says he'll "even set the wolf free north of the Wall where it belongs", Davos and the crew loyal to Jon (including Ghost) are ready to go down fighting.
Ghost stays by Jon's side as Melisandre attempts to resurrect him. He's the only one in the room when Jon awakens, as everyone else believed Melisandre had failed.
It's appropriate that Ghost is there for such a monumental moment. The pair are so connected that Ghost senses Jon's ~return~ even before he opens his eyes and breathes.