If she didn't oblige, he'd accuse her of cheating.
Coggin, who was 17 and 18 during the relationship, would also not allow his girlfriend to shower unless he "sat on the toilet seat watching her".
He pleaded guilty to two offences of coercive and controlling behaviour and was spared a jail term, although warned by the judge not to repeat the "abhorrent" behaviour.
He was sentenced to five months in a young offender institution, suspended for two years.
"If I were in your shoes, I would regard today's sentence as being your first and last chance, because if what happened to the complainant forms part of a pattern, it seems inevitable the next step for you will be prison," the judge said, according to The Sun.