You may have a problem with your self-image, not giving yourself enough credit where it is due.
You should meticulously list your strong points and accomplishments for yourself so that you will understand your abilities and achievements and not needlessly downgrade yourself. This will allow you to enter an affair in a more positive frame of mind about yourself as well as your partner.
If there is any question of quality in an issue between you and your lover, always take a bright and optimistic attitude, even if it is forced.
Whereas others tend to rush into some aspects of love rashly and unwisely, you are more cautious. You should probably try to be as free as possible.