Katniss's journey and who she met was deliberate and designed by Suzanne Collins. Since Peeta is so heavily interwoven into much of Katniss's trajectory, I think that Katniss's life would be a different story or would have a different backstory if she never met Peeta. But if we follow the premise of the book, arguably, if she had never met Peeta, she would have gone hungry as he would not have been there to throw her the bread that helped her and her family to survive during a time when there were no resources and Katniss was ready to give up on life. Given that context, Katniss might not have survived or she could have somehow made it and could have still found dandelions and learned to hunt. It's hard to answer because it's really the author of the story that gets to decide who lives, who dies, and what happens in the story.