submission
Being submissive is a natural reaction to a set of circumstances around your character and your experiences in life. It may be an innate need to serve or it may be a greater comfort and confidence in yourself if you have boundaries held by another, more dominant person. The fantasies that arise around submission can become obsessive if your needs are not met, and that can lead to frustration and an inability to take on life's challenges.
Stuck in a vanilla relationship with a partner who doesn't understand or expresses disgust: by the time you're in a sex-free zone, its time to fight to avoid a long term stand off or a break up. A constructive end to the relationship may be the best answer for some, or at least having the chance to examine that scary idea. Having your partner become your Dominant is often a long standing dream: it can happen, but most submissives approach it the wrong way. There is a positive approach that can be made, and it's not by pushing 'How To Be A Mistress' under her nose, nor is it by becoming increasingly submissive before her and hoping she enjoys the servile attention.
Too shy and too confused to start any relationship at all: retreating to a cyber world is a common response to the frustration of not being able to fulfil real life submission, and this is rarely a good option.
Seeking professional domination is often used a stop gap, a way of relieving the frustration. Sometimes the chance to submit and live out those fantasies may be worth more than therapy. But its expensive, it won't necessarily fulfil your needs and tends itself to become obsessive.
Life coaching (with a dominant edge if this is needed) can give you practical ways to either to alleviate or embrace the submissiveness and support the steps you need to take.
Castration fantasy needs its own page.