Complex sentence: At this time, Ukrainka was well on her way of becoming a pianist, but due to tuberculosis of the bone, she did not attend any outside educational establishment, writing was to be the main focus of her life.
Split into simpler sentences: At this time, Ukrainka was well on her way of becoming a pianist, but due to tuberculosis of the bone, she did not attend any outside educational establishment. Writing was to be the main focus of her life.