Why doesn't my phone charge?
MicroUSB ports on phones are delicate and can be prone to losing a proper connection to the power on the circuit board if you're not ultra careful about making sure to not stress the connection point (like having the phone plugged in and the cable is taut). 

My Wife has already gone through 2 phones and a laptop due to using them while the power plug is stretched and basically over time causing the power connection to come off the circuit board. 

This sounds like the issue you're having and the only solutions are if you take the phone apart and re-solder the loose connection (requires ULTRA fine soldering skills) or take it in for repair and they'll likely have to replace the mainboard.