So your saying that in RTD's Doctor Who Rose felt like her life was great and nothing changed about her or Donna just thought she was more then a Temp. Out of all the companions in his era, Martha was the only one that left. Rose and Donna had their lives revolving around the Doctor, they wanted to stay with him. Don't forget, Donna had been pushed to be with the Doctor by Davros. Amy had Rory and chose him over the Doctor. Clara had a life of her own and chose to schedule her adventures.