I was hoping to get some responses back first, but I don't want you waiting for an answer either. This could be separation anxiety. Here is a write up I have on separation anxiety. It covers ways to help a dog recover from spearation anxiety. I'll discuss some other things after the write up.
Separation anxiety can cause destruction, inappropriate elimination and excessive whining and barking. Some times it is just one and other times they do a combination of things. There are several techniques to help a dog with separation anxiety. First thing is to take your dog for a nice long walk before you leave, preferably 30 minutes or long. Make it a long, quick paced walk to tire your dog out.
Second is to use a low-key approach to leaving the house. Ignore your dog before you leave and after you come home for at least 5 minutes or more. If your house is like mine in the morning everyone is running around getting ready to leave. This has the dog in an excited mood and then suddenly she is alone. If this is the case, put him away from everyone, say in a bathroom until the frenzy is over.
Don't punish or shout at your dog when you come home and find eliminated again. When you do, you increase her stress level rather than reduce it.
You can provide her with small stimulating toys or toys that you can fill with treats. Sometimes leaving a TV or radio on can help a dog with this problem as well. Also remember to not reward a dog's excitement to you with petting and affection or even eye contact. You want to show her nice calm praise when she is being calm.
Another thing that might help is a DAP collar. These use a pheromone to calm a dog. See one here:
Practice leaving the house, opening the door immediately and rewarding her with a hot dog treat if she did not eliminate. This teaches her that you leave but come back quickly. Once she seems to not do anything when you initially leave, lengthen the time she must be calm for you to come back in. Change the time as well. Make it 2 minutes one time and 10 mintues another, so she never knows if you are gone for an hour or gone for 2 minutes. It helps hrt stay calm for longer periods of time, just be sure you reward her when he is good.
Another thing that helps is to do things that might make the dog feel you are leaving and then don't such as putting on your coat or picking up your keys. Or leave without doing those things. This helps remove things that might trigger the dog to become anxious.
These should help her separation anxiety and boredom and help curb her elimination. It will not be an overnight cure and will take work on your and your family’s part to be consistent in your interaction with her. Here is a site that also offers idea to combat separation anxiety.
Another option is medication, which is discussed on this site:
End of write up.
Some female dogs have a problem with incontinence after spaying which can make it hard to control their bladder. You can read more on it at this site as well as treatment options.
Your breed mix can have problems with the discs in the back as well which can lead to problems holding both the bladder and the bowels. Your vet can check for that with a myelogram or other imaging choices. Read about disc issues here:
An option might be to supply her with a sod patch that she can use when you are gone. You take a large pan like a kitty litter pan or even a baby swimming pool. You create a platform frame with wire on top. Place newspaper or other absorbent material such as wood shavings under the platform and place sod on top of the wire frame. Since it is grass, your dog will go on it. You can remove solids and can spray the urine so it moves through and down into the absorbent material underneath. This lets you use the same piece of sod for a while before needing to replace it. You do need to replace the material under the platform.
I hope this information is helpful to you. If you would like any additional information or have more questions please don’t hesitate to press the reply to expert or continue conversation button so I can address any issues you still have . If you do find this helpful, please take this opportunity to rate my answer.