That's why I said "if you can really mean it". And I know you can over-use it, but I'd rather someone say it too much than never say it at all. And common sense can solve the over-using problem pretty easily.
Explain to marshmellows that you do love them, but just can't afford a relationship with them right now. Put the ball in their court. Then they have the option of lowering their price, or possibly losing you forever. :P
It's also no fun hanging out with one of your bros when they're just thinking about their gf. I'd rather them just not bother hanging with us if all they're going to do is think/talk/day dream about their lady.