Why is Philippians 4:13 written as "I can do all things through Christ which strengtheneth me"?
In a nutshell, the verse is referring to the power of Christ (His all encompassing love for us, and power through us), not just "the man" Jesus.
The bible tells us in multiple passages that Jesus IS God, and God is not a "who". He is far more than that; words cannot describe His Love and Power. The members of the Holy Trinity are individual "persons", but simply referring to any of them as a "who" would be limiting them or putting them in a box.