Put yourself in the shoes of the ECO and keep it simple to understand.
Your wife completes her application first as she is the primary applicant, hence the success of your application is dependent on her visa being approved.
Your wife enters the total amount she plans to spend including the sum she’s contributing towards your trip. Her financial documents must show she can afford this figure, and she can explain the amount attributable to your expenses in the ‘additional comments section’.
You enter the total amount you plan to spend. You state the amount you personally have available, and provide the relevant evidence. You state the amount your wife is providing to you in the subsequent question(s) about who is paying for all or any part of the visit and how much that person is contributing. Explain further in the ‘comments’ section and/or your covering letter.
The ECO will have seen this scenario 000s of times. Just don’t over-think it.