My wife feels trapped in the marriage and she wants me to leave her alone. For some reasons, she seems to lose her passion in the marriage. When you tried asking her many times, she will shun your questions to answer you. When this is happening to your marriage, it is obvious that something is bothering your wife and you do not know what to do.
Your wife probably feels that her needs are not being met. She is most likely to be in a frustration of not knowing what to do and that is why she feels trapped in the marriage. She may also be worried or lost because she is feeling insecure too. If she wants some time to be left alone, just let her be. It will be worse when you try to force or pester her for an answer. You definitely need to find out what went wrong in the marriage, but you should not try to provoke her if she is not ready to share.
Let her know that you truly care for her and is willing to do whenever she needs help to make her feel secure and even let her know you are willing to make better changes to the relationship. If your wife tells you that she is feeling trapped in the marriage because of issues like freedom and trust from you, then you should self evaluate the treatment you give her. Are you not giving her enough space? Did you always doubt her on the things she does? Did both of you quarrel over any particular things over and over again?
It can be any reason that she feels trapped in the marriage. Most importantly, you have to find out the problems and work on it. Miscommunication is often one big misunderstanding that can create troubles to a marriage. There are always ways to compromise each other to make the relationship better. Other than that, keeping your marriage alive and interesting is one great success to lifelong marriage.