Just because you don't feel an earthquake doesn't mean it isn't shaking, that something near you isn't collapsing. Silence is often a woman's loudest cry.
When a woman closes herself in a world of silence, it can mean that…
… instead of hurting you or herself, she chooses to will leave things as they are. She withdraws, as she finds it pointless to talk about the problem.
… she is injured. Solitude calms her down and she knows that it will be better for her to be alone for a while and think about everything in peace.
… she wants to deal with the problem herself. She had tried to get advice from others in the past, but found that their involvement made things even more complicated. She knows that we have the power to solve the problem on our own.
… he has enough. Everything became too tiring for her. She ends up being powerfully and emotionally destroyed. He just needs space and time to himself.
... just maybe doing her lady things and her silence is just preoccupation. Maybe she's working out, she's at the beautician, with new friends; she is simply busy with other things.
... to you he doesn't want to confide his problems, even though he needs and misses you. She's thinking that you'll misunderstand her vulnerability, that you'll think she's weak. The pain of your potential rejection is greater than the pain of him not talking to you.
… she is selfless. She knows she hurt you and she doesn't want to open old wounds. It gives you and yourself space to think about the problem and where you stand in your relationship.
… may have been your last argument is really the icing on the cake. She is too upset to communicate and needs a break. She will come back, but leave her where she is.
… she is worried. About everything. Did she hurt you? Are you thinking about her? Should I have done things differently? Will you be the first to respond? She is overwhelmed with all the noise in her mind and tries to silence it by closing herself off from you.
… she is strong. She knows it won't help her to interfere. She had done this before and things didn't get any better. As much as he wants to talk about it, he knows it's best to back off and leave things behind.
However, silence is almost never a good thing, because when you choose not to speak, you let people fill the void themselves, and they usually fill it with their thoughts either with fear or doubt.