There is no "Why?" for an addict. That is like asking someone "Why did you get cancer?" Oh, alright, there may be triggering events but why just does not compute. When I got out of rehab the house was just as I left it. Same dirt, fruit and vegetables that had rotted in place, dust everywhere, unwashed dishes... OK, my husband was devastated, and very supportive of me, but I was a little shocked at the mess.
I have come to regard that as a sign that I did have a place in our life, and while I can't do everything, I have been able to do a little each day. Even if that meant nothing more than washing one plate. That is enough in the beginning. It will give you a sense of accomplishment. Time will take care of the rest as you do what you need to do to stay sober.