Wolves would never abandon a member of the pack - they are intensely social animals that rely on each other for everything. They are extremely loyal and devoted to one another. This includes feeding, protecting and caring for sick or injured pack members - wolves have been known to recover from serious injuries like a broken leg or jaw because of the support of the pack. For a lone predator, such injuries would mean death since they would prevent hunting or feeding (wolves with a broken jaw cannot feed normally, by tearing chunks of flesh from a carcass, but the others will regurgitate food for a wolf so injured, just as they would for their cubs).
In the past, wolf hunters would use their loyalty as a way to catch them. They would set a trap and capture one member of a pack - the others would then come and try to help it, enabling the hunter to catch them all.
A wolf pack is basically an extended family, and usually has less than 10 members, though up to 30 have been recorded. The pack is led by a dominant pair called the alpha male and female - they mate for life and are the pack's only breeding pair. The rest of the pack is made up of their siblings and/or offspring. Below the alpha pair is a second-in-command called a beta wolf. Then come mid-ranked individuals, and at the bottom of the heap is the omega wolf, the lowest-ranked pack member. All members of the pack help to hunt, defend the territory and raise the alpha pair's young.
The strict heirarchy of the pack is maintained through displays of dominance and submission, which eliminate the need for physical violence. A dominant wolf will stand tall with its head up, ears pricked and tail raised. A submissive wolf will crouch low, with head down, ears flattened and tail tucked between the hind legs. It may even roll over on its back as a gesture of complete submission. Members of the pack are very affectionate towards each other, often licking and nuzzling, and play together every day. Maintaining the bonds between them is essential for their survival, and they have been observed to mourn when a member of the pack dies - they cease play for around 6 weeks, and howl often as though calling to the missing member. There are even cases known in which, when one of a mated pair dies, the other will stop eating until it too dies.
I used to be a zookeeper and have studied animals all my life.