Grigor Dimitrov 

Bulgarian tennis ace Grigor Dimitrov has been at the receiving end of many sour break-ups. He was linked to American tennis great Serena Williams in early 2012 and Maria Sharapova later that year, where the duo enjoyed a two-year romance. Dimitrov has learnt from his mistakes of making his relationship public, and now wants to ensure every moment with current girlfriend Nicole Scherzinger is spent in private.