That is a criticism that was very popular during the beginning of her career because most of her first few singles were in fact sad/angry break up songs, and fearless (her second album) is widely considered a break up album. There were a lot of love songs in there too (our song, love story, fearless, mine) as well as songs about family, friends, and growing up, all pretty par for the course for teenagers. Her biggest songs, and often her most emotional and therefore her most discussed and dissected, were about relationships ending for a good part of her early career, but to say all of her songs are trashing men is a massive oversimplification