I'm so sorry to hear about your Daughter and boyfriend. I know he is devistated, my son was too, couldn't understand how you could share so much with someone and they could just walk away. We have had ups and downs since the break up, he found out a few days ago that she is dating a friend of his, so that was a bad day, but then today he informs me that he has a date with a girl and seems happy. I worried myself sick, and in the end they do move on. I'm so happy that he has you, does he have alot of friends to keep busy, encourage that, its so sad he doesn't have family to lean on, that is why you are so important to him. I know what you mean, its not just them breaking up, you had time invested with this boy too, just like I did with my sons girlfriend, its sad to see it all end, because you become close, we had 2 years invested, she was like part of the family. I just keep thinking it wasn't meant to be. They are so young, she wasn't ready to settle down, and maybe that is what your daughter is going thru too, maybe in the future she will see what a great guy he is.
I don't think I would give him false hope.. but you could encourage him to meet new people, and to go on with his life with dignity and respect. A strong person is so much more enticing than someone who you pity. Just be understanding, there are alot of books out there dealing with this subject, maybe you could get him one as a gift, on amazon there are several books and people have rated them and say they have really helped. I sure hope he finds his way, I think if you abandoned him that would just be too much, and I think in time he will slowly pull away.