break the back of
Verb
Meaning
(idiomatic) To complete the greater part of (a project).
I've broken the back of painting the shed – I'll finish it after lunch.
(Can we verify this sense?) To overburden (a person).
Source: en.wiktionary.orgSynonyms
Examples
As we break the back of this pandemic expect to see a lot more overt military assistance.
That's the kind of debt that can break the back of most small businesses.
The editorial argues “that it would be wrong to believe that all this will break the back of the students’ movement.
If Intel was able to own the Mac OS and make it available to all the OEMs, it could break the back of Microsoft.
I want to break the back of the gun lobby.