Do You mean...
And guys,maybe boobaa said it in a bad way but actually she should lose some weight. It's not only a cause of looking good,but health. Do You know how chubby people die young? Whole fat is putting a big pressure on heart, and she doesn't have just 5 kg too much... I don't laugh at her,it's just really important for her future long life.
People shouldn't avoid talking about somebody's obesity just because it may hurt his or her feelings... It's a big problem today.
And about the OP's situation... To say it quick , I think Your bf wants sex,and it might be important for him... Even more than staying with You .And if You already did 'cyber sex' , You actually lost Your mental virginity.So where is a problem to lose it in a physical way? If You don't want to have a sin,sorry but You already have.You can sin also just with your thoughts .