Bearded dragon died... duno what to do?

My beardie who was 8 years old and rescued. He was 2 years old when i go him and he was deformed due to lack of calcium and UVB. Iv recently graduated as a animal biologist and i had her for 6 years she had the best life but all of a suddent she wouldnt eat (i fed forced her but it was hard) she lost all weight, she was tested negative for parasite. Im finding it hard to cope with, she was my first reptile and i miss her so much. i dunno what to do.