First, it’s okay for your wife to change — people evolve, especially after big events, so that’s normal. Perhaps come at that part from the perspective of getting to know each other again (it’s normal for you to change too).

Next, don’t listen to what your wife says she wants. The bottom line is she feels overwhelmed and unsupported. This cannot be solved by you trying to fill that gap, because she wants emotional support from you and needs physical/material support from somewhere else. Here’s what she more likely needs:

1. someone she trusts (not you, a family member if possible) to watch the kids for an entire day or as much as they can handle. If it costs some pumped milk, so be it — but clear it first.
2. Someone else (still not you) to clean the home while the kids are out, whether that’s daily stuff like clutter/laundry/dishes or weekly stuff like wiping down toilet seats and mopping or both.
3. You to take her somewhere out of the house and away from kids. Could be a park since not a lot is open now. When she is able to actually think and feel without getting overwhelmed, the two of you will likely be able to have a real conversation (not reactionary snapping due to exhaustion) about what’s really going on. Then you can talk about solutions. During this time she may start out very prickly and possibly even resentful, but have patience and keep responding with love and kindness until she sees you are on her side and feels safe to share her feelings.

Good luck.