If he is - and from the comments, I would hope that it's unlikely - I would be looking to get a new boyfriend.
You know he can do something about coming sooner than you both want? Have a read of Bernie Zilbergeld's books, 'Men & Sex' or 'The New Male Sexuality' - the latter is the second edition of the first, originally titled 'Male Sexuality', but there's no much difference. At least one person is usually offering one of them for 1p+postage on Amazon (it's M&S at the moment, I see...) It has a very good programme of exercises, alone and with a partner, for getting control over this.
And are you doing other stuff in bed that you do enjoy?