You need to relax take a deep breath and start over. You need to contact your local S.P.C.A. and ask them for a referral to a behavioralist. There are many in your area. I really think some intervention by a professional will help you and everyone involved. Please don't give up. Here is a link to some others in your area, start making calls, be proactive and believe that you can solve this. Sounds like your at your wits end and your own self esteem is low at this point, and I don't blame you one bit.
If worse comes to worse ask your vet or a local Yorkie rescue to help you rehome your girl - if you don't find a new home here.
I think you love your pups and I think you would be better off trying every last thing to make this work, you are very torn and I think a little positive energy will go a long way for you..but again, if you must rehome please do it carefully.
Good luck and don't give up.
http://www.google.com/search?sourcei...+in+houston+tx