These signs are similar but also very different. Gemini is always using his quick mind to analyze people the second he meets them, and Cancer is always feeling people out based on their emotions. They like the mystery of people they don't know, and they will enjoy getting to know one another as well. They will come close to understanding each other, but never completely. Gemini will always have a hard time understanding what she is feeling, and Cancer will have a hard time understanding what he is thinking.
One thing she should avoid in her moods is to not talk things out with him. Geminis are typically quite cheery, but this will drive him wild. Geminis are Mutable signs and like to talk everything out. He will get frustrated when she gets in her mood because it is rare that he will be able to get her out of them. Poking and prodding her for reasons of her moods is not going to help the situation at all. If you love her, let her know you are there for her and she will come around. I know this may drive the Gemini a little nuts because they like to fix things when they are broken, but some things are better left alone.
If she could she would give him the Moon. Cancer women love to nurture, care for, and protect the man that they are with. The only time he will lose this a little when they start having children, because they will become her main focus. She is the woman that will cook and clean for her man. She will make him laugh with her kooky sense of humor. One thing that will be hard for her is his ever changing mind. This woman likes to make things, and make things happen. She has a hard time doing that with him when he is always changing what he wants. This can lead to a few problems in their communication. She wants to know what he wants, but the problem is that he doesn't know what he wants. It is hard for him to make all of his dreams into one solid goal to work towards. When she gets frustrated you will see tears. If she is truly hurt she will crawl into her shell and not come out for a few days.
These two operate at two different speeds. She is slow and cautious, and he is fast and reckless. Regardless of how they are outwardly, that is the speed and process of their mindsets. She at times may feel a little insecure with this man's tenancy to be a little all over the place, so at times she will cling. If he is financially unstable, it will be even more so. As I have mentioned in a previous post the Cancer woman has very specific wants and needs.
Geminis are rarely pack rats seeing that they get rid of everything that they do not need anymore. She is quite the opposite. She likes to hold on to everything for dear life. She is a very sentimental woman, and likes tangible items for the memories. This is how she is with relationships as well. Cancers will stay friends with someone long after they meet them. Geminis relationships with people are a lot more casual than hers are. She had a very hard time understanding this about him. She loves familiarity and feeling safe with people that she has known for a long time. When she is in love she will not be able to toss it away like a lot of people can. Hers has to wear away, which can take a very long time for her. When a Gemini comes out of a relationship he does a lot better off not holding on to things that slow him down. If it's over, it's over. He feels this way even to family. If someone even of his blood is weighing his light heart down, he will cut them out. He is much of a free spirit, and isn't one to be tied down but she may be just the girl to do it. If she learns to let go every once in a while and let this man have his freedom with love being their tie, they will find a peaceful, warm, and beautiful relationship.
When it comes to sex for these two, it will be mentally and emotionally erotic. Her tenderness, affection and imagination are a good match with his sensitive and sexual nature. Sometimes there will be a few things missing. Gemini needs to slow things down a little bit for her. Come out of the clouds and hold her a little longer than you usually do to make her feel safe and secure. When the full moon is out, you may have your best experiences that lead to a deep and dreamy connection. This man has multiple personalities inside of him, and on the full moon she will be able to tie them together in a mysterious way creating an extremely satisfying experience.