I've met a new and exciting man. This is my first real relationship. However, his invariable approach to love-making is to reach his orgasm and then go straight off to sleep - despite the fact I have not climaxed. Is this normal behaviour for men?

Well, its less common than it used to be, thank heavens. Really, that kind of approach is extremely thoughtless and selfish. Frankly, I suggest you tell this bloke if he wants the relationship to continue he must make absolutely sure he satisfies you in bed.