Hatching Quandry

I know how you feel, I got very carried away this summer hatching eggs and got very attached to them all.
The way I like to think of it is that the people who buy the chickens will probably grow just as attached to them as you have. If people pay for something they usually take care of them or they would be throwing their money away. It would be different if you were giving them away.
You usually get a fair idea how much experience people have hen keeping, if they are novices give them the option to ring you for advice.
As for the boys, it is heart breaking, I got alot more boys than girls.  I have been lucky enough to find a very nice man who takes my cockerels and pairs them with birds he buys cheaply from mart and sells them on as unrelated pairs - at least that is what he tells me lol 
Go to your local mart, you may be able to find somebody to do the same for you. If you start chatting to sellers and buyers they may know someone.
It would be a shame not to hatch anymore for you and your girls

I havnt ever hatched my own chicks but its something I would worry about is what to do with the male chicks.  I am a terrible softy. 
I think once you sell some it will get easier when the next lot come along.  Think of the happiness you are giving other people.  You can always give them your phone number so they can keep in touch with you if they have any problems as rileyfin said.