I am so sorry to hear of your sweet Chalupa's passing. It's always so hard to have a beloved pet die. RIP little girl, she will be waiting for you at the rainbow bridge.
Give yourself time to grieve and you may find you are able to love another. I have had so many dogs, and a part of me dies with each of them, but my heart is big enough to welcome another in. But, if you find that you can't, that is ok, too. Do what is the best for you. *hugs*
Pam's Chihuahua Sanctuary