Cancer is the sign of the Crab, a creature fully equipped to handle the crashing ocean waves with the help of an unbreakable outer shell. Your shell is your protection, your home and your comfort, and behind it is where you often keep your feelings safe from the outside world.
You use your claws to hold onto the past, which means it’s hard for you to let go of people close to you. Therefore, you want to nurture and protect your loved ones within your shell -- just as much as you protect yourself, if not more. If you’re not careful, you can be overbearing.
Your motto could be, "A good defense is the best offense." While others may see your tendency to retreat from problems and issues, you use it as your special defense mechanism, hard-pressed to reveal your true emotions in fear of getting hurt. This can lead to resentment later down the road, however, so it’s important to be honest and open about your feelings.
The habitat of the Crab is water and the changing tides that surround it. While the water provides food and nurture, on the surface it appears smooth and still, without movement. Underneath the surface, however, an active life exists.
Astrologically, the Water element symbolizes deep emotion, an endless cycle of feelings that connects the present with the past. Sometimes the waters are so deep that we cannot put those feelings into words.
The 4th house is related to the nurturing mother, especially early in life. This is the house of childhood surroundings. It is where we retreat from the noise of the outer world.
As the key planet of Cancer, the Moon symbolizes our basic needs -- how we need to be nurtured and how we nurture others. The Moon is always changing, not even the same two nights in a row. It races around the earth once a "month," and as such we are familiar with her regularly repeating patterns. Women's menstrual cycles are naturally tied to the lunar rhythm, putting them in closer touch with the subconscious realms of the Moon. But to man and woman alike, the Moon is the key to our feelings and our emotional cycles.
You have an innate ability to nurture others
You fear the past repeating again in the future