I Just Got Out of a Detox Center and Relapsed, What Should I Do?

Unfortunately, the detox center was very pricey and we aren’t made of money and I have NO insurance. I went in to detox from alcohol among some other harder drugs. When they released me, I was still withdrawing severely so I used and it did help. I just feel bad because it seems like the detox center was a waste of money. Should I go to rehab even if it’s expensive and my Mom would have to dip into her retirement or should I try NA or AA? Any kind advice appreciated. I didn’t choose to become an addict.