I am Libra, My Lover is Pisces
There are many ways this union could work, even though astrological textbooks might turn down their nose at it. Pisces is a creative and highly sensitive sign and would relate to your refined nature. You both love poetry, music and art. Your Pisces will want to go out and experience life with you. But your Pisces will also want to have periods of intense privacy. Pisces won't be trying to get away from you so much as from life in general; they need to make sense of it all in solitude because the exertion of everyday life can harm their psyche and dull their delicate nervous systems. Of the two, you are the realist and better at finding practical solutions, and your lover will provide you with the inspiration and vision to do so.
Pisces are deeply emotional, highly sentimental and romantic. They want to discuss the meaning of life, their feelings about religion, the suffering of others, and how to help. As an air sign, you may find these discussions stimulating, but Pisces won't care as much about what you think, so much as what you feel in your heart. Get too analytical and you'll lose them; they need to sense authentic feelings in you. This may or may not be exhausting for Libras, who like to take what they see on the surface, instead of diving down to the ocean floor where Pisces exist. Pisces is the sign of dreams and the subconscious, and will help you explore realms you never considered. This process will change you for the better, if you allow it. You are a cardinal sign, and therefore aggressive about searching out new experiences. Pisces are very adaptable, so they will give you no problems in this respect. Pisces will be happy to follow your lead as long as he or she gets enough time to him or herself.
This soulful lover will never value the material world the way you do, however. Pisces are of the spirit and soul. Faced with a financial windfall, you would buy a painting or rare jewels; Pisces would rather pay debts, buy creative tools, and give the rest away to charity or friends in need. Thus the area of joint resources could be an area of struggle, but since your Sun lights up Pisces' house for joint resources (8th house), of all the signs, you may be the most beneficial for Pisces' money. You could at least set up a good program of savings for his or her retirement -- something Pisces rarely see as a high priority.
Sexually, you will be touched by the depth of feeling you experience together, the care your Pisces takes in giving you pleasure, and the exquisite aura that will be wrapped around you.
This is one lover to have and to hold. Give it a good try.