2nd baby is good? My child and family?

I am 38 M, married almost 10 years ago. We have a 8 yr old daughter. My wife (36yr) wants 2 baby where I don't. We are from middle class family where I have decent job in IT and earning is sufficient handful of ear for 3 of us (lesser than market standard). Is 2 child is good for my child and family? Considering child's growth with current my financial and surrounding growth. I have fact to denie from 2 child where wife has multiple reasons to have 2. Need your help and support to understand what is good. I have no options to visit any psychiatrist with her, I am available online. Bit more background, she is interested in sex only for child else big no where I have lot more hunger for ultimately I land-up in masterbating.