I work at a mid-sized business-first company with a lot of tech debt and very unstable systems. My on-call week is a 24x7 hellish nightmare for an entire week (Monday morning to next Monday morning). This means that I cannot go out for even a 10 minute walk, because the "SLA" is "5 minutes, hands-on-keys", regardless of the actual business impact some issue is causing. It also means that my wife can't sleep peacefully for a week because of the my being paged round the clock (Edit: now I sleep on the couch during my rotation).

It has often been raised as unhealthy, but the management just puts it back on the developers saying we need to build better systems. The issues themselves to get fixed eventually, but the rate of growth of systems is just overwhelming, creating problems faster than on-calls can resolve them.

Apart from the on-call work, I still have to meet my sprint commitments. What's more, since my joining predates the on-call process, my job contract does not state requiring to work after hours, especially weekends. I know that some companies offer extra pay for on-call duties, but mine does not.

Is it always this bad? How can I make my situation better?

Edit: Thanks for the words of encouragement, everyone!