We cannot support a baby right now. Is that the explanation for why he went limp?

Please explain ???? Your statement & question do not give enough info to respond. I cannot tie your finances to any issue at all. Baby went limp?Lots of possibilities on babies going limp, other symptoms ?
Psychological. If you are talking about your husband going limp, yes, stress and emotional issues can cause problems with erections.
What went limp??? Your penis from depression or stress anxiety? A baby? What are you talking about?