Maybe she had a bad experience with other dogs that scared her?
For winter? Like playing with other dogs during winter or being socialized to the changes in winter (coats, boots, sleds, shovels, etc)?
I can imagine your weather being bad in Canada, I'm from VT and it gets pretty bad here xD I don't know what it's like though where you live but I still bring my dog to off leash areas, dog parks, etc just not for as long of a period. My dog's very dog friendly but she's also getting old so she can be snappy with puppies (my neighbor's sheltie pup once tried to herd her. She did not like that at all xD)
As for winter socialization with a puppy... haha, that's a problem because there's a 4 month socialization period and people only have puppies for two of those months. If you get it in the summer it won't be socialized well for winter and if you get it in the winter it won't be socialized well for summer. For winter objects just wearing coats and boots and showing them shovels and exposing them to as much as possible that you can always helps.
Techno- Red VT male
Peanut Butter- Cambodian red CT female
Mr. Brightside- Multi salamander HM male
Nemo- Purple salamander PK male (with a special fin!)
RIP Charlie, Flame, Indigo, Juliet, St. Jimmy, Reese, and Temeraire
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