For what it's worth, I live with 2 retired greyhounds (one is 2 and the other is 4), and have had two others before who have passed away. Taking care of them gives me a feeling of responsibility I hadn't shown for myself in a long time. Knowing that they can't take care of themselves sort of forces me to give attention to them at a time when I can't seem to give attention to anything else. Obviously I don't know about your situation enough to say, but if you *can*, I'd urge you to consider your doggie not as a burden to add to your already complex life, but as a cornerstone to a more solid one.
Much love, and good luck.