Why so downcast when you should be rejoicing?

Joni Eareckson Tada was a normal teenager who lived an active life. She enjoyed horse riding,hiking,tennis and swimming. At the age of 18 she had a swimming accident which left her paralysed from the neck down. She wrote herself off in her present cpndition, feeling she had nothing to rejoice about and experienced bouts of anger,depression,suicidal thoughts and the likes.
Do you also feel the same or your case is similar? First you have to place value on your life and neither can we act beyond the value we place on ourselves. Indeed anyone whohas a diminished sense of value,will live below their potential.