I read Plath early on, and loved her from the beginning. I always found her tortured. Her poems are first rate. I think it's probably a mistake to idealize desperate and suicidal women as feminist icons, however. There are quite a few wonderful women poets, such as Maxine Kumin or Louise Gluck who are very fine poets, haven't killed themselves in the process and have lived lives that can be good examples for women poets who want to survive and thrive in the world.
Being crazy is over-rated.
Sylvia Plath is not over-rated. Being a victim is.
Ms. Plath appeared to be suffering from both Bipolar depression and Borderline Personality disorder. These are two rotten hands to be dealt. The odds of a person with either diagnosis having problems hanging on to life are high. With both problems, it is very high indeed, and there were no decent therapeutic approaches available for dealing with this combination at that time. There are better odds today, but blaming her husband for her death suggests unpleasant and probably untrue things about Ms. Plath. It is her resiliency that was difficult for her, it was not that she lacked ambition or drive .
Ted Hughs was also a very fine poet himself, possibly as fine a poet as Ms. Plath, possibly better if a sympathetic reading is given to his whole body of work. He was certainly a better critic, and Ms. Plath had a high respect for him for good reason, not because she was denigrating her own high value as a poet and a person. She evaluated his writing accurately. His modern feminist readers might consider giving him the same open reading that she did.