你不忍心看到你曾经精力充沛的（有活力的）母亲由于中风使她几乎残废而过着痛苦、受限的生活!
you是主语,cannot bear 是谓语,
see your once vigorous mother living the painful,limited life to which the stroke has condemned her全部是宾语
your once vigorous mother living the painful,limited life to which the stroke has condemned her是see的宾语
once vigorous 是修饰mother,在这里作定语
which the stroke has condemned her.在这里补充说明“母亲过着痛苦、受限的生活”是由于中风所造成的
condemned原意是“谴责,报废的”在此处译为“使…残废”较好（中风使她几乎残废）