"Why wouldn't you travel by main roads?"

Episode 4, Of Banquets Bastards and Burials - Yennefer

Alright. Now it's time Yennefer's side of the fourth episode.

Yennefer and Queen Kalis are in a coach together.

Queen Kalis is lamenting her situation, and Yennefer is largely ignoring her.

"I know what they say, "Poor Queen Kalis, another girl."
...
"Why don't you stay in Lyria? Keep me company."
...
"I envy you. Truly. A king's mage. How splendid!"
...
"Oh, come, now. We've been traveling together for days. Speak freely."

Kalis must've been queen for at least a couple years but Yennefer seems to barely know her. Why? Some possibilities:

1) Kalis was initially hostile/avoidant. Whether or not Yennefer and the king actually were fucking, Yennefer says that's how at least one king sees it and the sorceresses are all "works of art" who get introduced to their future employers by dancing with them at a party. (The one other king we see doesn't seem interested in his sorceress, but that's a guy where it's a plot point he's not interested in anyone due to holding a torch for his dead sister.) At the least, it's probably what everyone assumes is true, and even if Kalis was marrying for entirely political reasons, she could still be uncomfortable with it, especially right after marrying and arriving at the court. (And given she goes on to say, "Bastard cares more about his hounds than he does me." it does sound like she expected and wanted at least some degree of an actual relationship.) But by this point it's become clear that it wasn't a matter of her husband liking someone better but her husband not giving a shit about her, so she doesn't have a reason to resent Yennefer.

2) Kalis is not an actual player in court politics and doesn't know anyone. If she's already had enough children that people are gossiping about how none of them are male, she's also likely spent most of the time at court pregnant or recovering from a pregnancy. She evidently hasn't been asking things of Yennefer or causing problems Yennefer needed to deal with, and the fact she thinks she has to say "I know what they say" sounds like someone who's isolated and sidelined. (The fact she's being sent off with only her newest child and not the rest of them would fit with the idea she has no particular say in anything and is considered irrelevant by everyone else.)

3) Yennefer had largely stopped interacting with any of the court by the time Kalis arrived. We see here she's barely engaging with Kalis and everything she says during this episode suggests her depression, and the withdrawal that likely went with it, has been going on for a while already. It's hard to say how old Kalis is, but she certainly looks young, and as this is the only time she appears it seems less likely this is a matter of casting someone able to play the earlier scenes and then forgetting/not wanting to put on makeup to age them them in later ones.

Worth emphasizing is that "We've been traveling together for days." means whatever other factors were in play for Kalis, Yennefer's been sitting around silently even when there was nothing else to do but talk. We don't know if this was true for the entire time Kalis was at court, but by the present, Yennefer is extremely withdrawn and it's likely she either hasn't been interacting with anyone or, if she has, it's been limited to people hunting her down and making demands.

Let's recap what Yennefer said she wanted in the third episode. Istredd accuses her of three things. She agrees to two of them, disputes one of them, and adds another of her own.

First,

Istredd: "I was going to Temeria for you."
Yennefer: "That was your decision."
Istredd: "You really think I wish to waste my days gossiping at court? That's your fetish, not mine."
Yennefer: "A true man would state his desires."