Sentence:  Mrs. Weston was exceedingly disappointed—much more disappointed, in fact, than her husband, though her dependence on seeing the young man had been so much more sober: but a <WSD>sanguine</WSD> temper, though for ever expecting more good than occurs, does not always pay for its hopes by any proportionate depression. It soon flies over the present failure, and begins to hope again. 
Meaning of the word marked with <WSD> tags:  Anticipating the best; optimistic; confident; full of hope. (from early 16th c.)