I'm new here and am an amateur astrologer but I'll take a stab at the question. Look at your Venus and your Mars. Venus is how you present yourself to attract a mate, and Mars represents the type of mate you are attracted to.
Your Venus is in Scorpio, which means you're attractive, mysterious, and cautious. The reason that you are probably single is because you're overly cautious, and have a deep fear of being hurt as most Scorpios are. (I know how you feel, I have a moon in Scorpio). People with a Scorpio-like love nature need to learn to be less guarded and let people in.
You have Mars in Leo, which means you're attracted to mates that are charismatic, outgoing, confident, ambitious, proud, passionate, leader types. You're looking for the yin to your yang. Since most of your planets, (9 out of 10), are in the bottom half of your chart I assume you're shy and introverted. You seem to be attracted to people who are extroverted and outgoing.
You can also look to your 7th house, which as you can see is empty, so we look to your chart ruler instead. The ruler of Pisces is Neptune, which is in your fourth house. Here's what cafeastrology says about Your 7th house ruler in your 4th house: You seek a partner who is nurturing, caring, and domestic. A feeling of security in your close personal relationships is extremely important to you. Fitting in to your sense of home and family, and your set of traditions, is important to you in a companion. You seek someone familiar and comfortable. Your life partner may be the one who provides a home base for you--a sense of comfort and security. This position can suggest that your relationships tend to mirror your own parents' relationship, either in an unconscious attempt to fill emotional needs that went unfulfilled in childhood, or to cling to your roots. You tend to feel threatened when others don't support your most basic of values.
Hope I helped