Thanks for making your problem more clear, Mandeep. What you wrote at the start really made no sense. You need to give the background to the situation, then clearly explain exactly what happened. If you don't do that, you will either get no responses from the Forum, or those who do respond, will misunderstand you.
Yes, it's nice to think that your partner would want to be 'straight' with you.... and not mislead you. But there's always two sides to every relationship problem. Maybe if other people (like her workmates) asked your wife about your relationship, she would say something very different from what you would say.
It's possible that you do things that really annoy her..... and this tendency to 'lie', or mislead you, is her way of getting back at you.
The solution is to have a relaxed discussion with her and find out if you do things that frustrate her. It sounds like she can chat openly with her workmates more easily than she can chat to you (perhaps).
But she won't open up if you sound indignant, or seem to be challenging to her. Maybe start by buying her some flowers.... and say that you aren't happy with what's going on in the relationship..... and that you think that it might be mostly your own fault. Ask her if she can she help you to understand what's going on.
Lying is usually used to get around difficult problems, or out of difficult situations. The challenge for you, is to find out what those problems are in your relationship.