Very few people would open up a separate bank account for their wife, who is unemployed. Most couples in which the wife is a housewife, only have a joint bank account. Not only that, you found a way for her to have a source of income... very good, I'm impressed. I'll also commend you because you not only bought her one car, you bought her 2. Some men might give their car to their wife, then buy a new car for themselves, since they are afterall the ones earning the money. She sends money to her parents, and you don't question it, good. I think you have tried your best to provide security and acknowledge that she too has rights and freedoms.
But it seems like money is on your mind: you opened up bank accounts, you took her on all these trips, you have a big home, she went home loaded with gifts for her family, she goes shopping, and she sent $2500 to her mom. For your wife to say, "I don't know if you have any money for me or not"- could mean SEVERAL things.
Maybe your wife thought you were rejecting her trip by saying that it needs to be discussed first? For her to think about buying tickets to Pakistan for only the kids and herself, NOT you, means that maybe there is some distance in the relationship. What is the cause of the distance is what needs to be figured out. Can you think of a reason why she wouldn't want you to travel with her, or why she might think you don't want to go with her? Do you not spend enough time with her that she thinks you would not be interested in going?
One of the things you have to realize is that women have a tendency to give the silent treatment, I do that myself. But that doesn't mean that you should fill out separation papers. Just like that, a woman can argue that the man never understands her. *And why do you feel like ending the relationship?- is it because of the way she handles arguments with you? She isn't abusive. It has to be more than that. *
She knows that if she doesn't cook for you, you can always buy food from outside because you have the money. Tell her that she cooks well, can she pleeease cook tonight, you want her food. If you can't tell her that, then write a note saying that. Tell her that you're her husband, you're responsible for her protection and you need to know the details of the trip.
If you think that you two cannot sort your problems, then go to a marriage counselor or speak to an imam.