The singer-and-actress started dating her back-up dancer last autumn just a few months after her seven-year marriage to Marc Anthony ended in July 2011 and the pair met through working together. However, Casper - who, at 25, is 17 years younger than his superstar girlfriend - insists there were no romantic sparks between the two of them initially.
The 'I Need To Know' singer - who has four-year-old twins, Max and Emme, with Marc - said: "It can be difficult for anybody who has to stand by my side ... But at the end of the day, I know that I deserve that (to have love)."
Jennifer is currently on tour with Enrique Iglesias - who appears with her for the 'Nightline' interview - and Casper is the head choreographer for the concerts but Jennifer insists it isn't tough to work with her lover.However, she admits it has been difficult when she has worked with some of her previous partners - who include P. Diddy and Ben Affleck.
Speaking about working with her lovers, she said: "I've done it many times and it's difficult with some people and with some people it's easy. It just depends on the personality of the person."Casper insists Jennifer is good at taking direction from him, but ultimately "she's the boss".