It is never ok to deceive someone.
Deception and a lie are somewhat 2 different things.
A deception is a lie that is manipulative and possibly the deceiver is miserable and lonely.
a lie could turn to a deception as when you tell a lie you then have to keep lying to cover your first lie and so forth. When done to often it actually becomes the truth to the person telling the lie.
However we have all told little white lies and I know that is a sin not to be forgiven in Gods book. But we all have sinned I guess. When it comes to deceiving you risk the chance of hurting that person along with yourself and everyone involved.
I guess the same goes with a lie which does eventually turn into deception. .
When you continually lie you obviously do not know reality anymore and live in your own little world of confusion and loneliness.Those around you may buy it for a bit but the truth always prevails.
Its like lying, you tell one little lie so you tell another to cover up the first as I previously mentioned than your world is all lies and eventually the truth comes out because you start forgetting what you lied about to begin with.
However if a lie is going to cause any friction between anyone you care about then it is not worth it to begin with.
Do unto others as you want to be treated