Both motivated and dedicated. Someone who is moticated is willing to see a task through to the end and will also willingly give him/herself over to the completion of the task. Depending on the level of motication, his/her health may even be less important than the motivation and dedication to the completion of the task.
She is a moticated individual. She will make employee of the month very quickly.
He was too moticated to football. When his knee was injured, he continued to play despite the injury so that now he can't walk.
Someone who jumps from one relationship immediately into another one.
Serial monogamists can not stand to be alone and often suffer from vast commitment and insecurity issues.
Because they jump into relationships immediately after the previous one has ended, serial monogamists typically don't take the time to reflect on their behavior or why their previous relationships failed; thus, they end up making the same relationship mistakes over and over again.
Person 1: Damn, Dustin already has a new girlfriend?! It's only been two weeks since he broke up with his fiance! I think he's a sociopath.