I was like your wife, severe problems with guilt and stress. Especially as a mum, as a jw you are supposed to keep the house very clean and be on top of everything there, support your husband in his privileges, hospitality etc, teach your children, work (at least in my case) , attend all meetings, prepare for all meetings, ministry as much as possible and help your kids to do the same. Then I would feel guilty and extremely stressed if I slipped up in any of these areas. Inevitably there would be some item on the assembly about 'doing more' with some demo about a super pioneer disabled mum of triplets and I'd end up in bits afterwards. It's pure mental torture.
Try to help your wife to start enjoying life, ask her is this what God really wants for her to be stressed, guilt ridden, loaded down, or to be happy and healthy and heartfelt in anything she does for God. It's men who put the burdens, rules and demands on us, nothing in the scriptures has it so. The only statistics counted converted new believers, never hours.