The Moon and Venus are feminine planets, and often play a role in the kind of partner we desire. The Moon represents our emotions and what makes us feel secure, while Venus represents how we give and receive love.
When these planets are in square/opposite aspect to one another, our emotional needs are at odds with our needs and capacity to love. This can cause many problems, as it is difficult for the Moon square/opposite Venus native to have both needs fulfilled by just one person. For example, say I have Moon in Aries square Venus in Capricorn: on one hand, I am emotionally fulfilled by aggressive, direct, and passionate people. However, aggression and passion to not “agree” with my Venus in Capricorn nature; it is unattractive to me, as Venus in Capricorn prefers shy, stable, drama-free mates.
Also, we can think of this in terms of synastry: if my partner’s Mars is in Capricorn, and therefore is in conjunct aspect to my Venus, I feel a tremendous sexual attraction to my partner. However, it would also mean that my partner’s Mars squares my Moon, which leads to heated arguments and hurt feelings. As a result, the native finds it difficult to find a partner who fulfills both their Moon and Venus needs, and might choose to have two partners: one who makes him emotionally secure, and one that makes him feel loved and attracted.
This can also indicate a Madonna-Whore complex; the native may have the inability to see his or her partner as both a nurturing type (moon) and a sexual being (Venus). To solve this dilemma, the native may choose to take on two partners in order to have these needs fulfilled.
Of course, not all Moon square/opposite Venus natives are infidels! Nevertheless, people with this aspect find themselves “giving up” one planetary need at the expense of another in some way. They will disregard their Venusian needs for their Lunar needs, and vice-versa. For instance, the native will ignore his or her emotional needs in order to feel attractive and valued, or will ignore his or her need for approval to satisfy her needs for security and comfort.
Peace and harmony are very important to these natives. This is why many people with this aspect can be regarded as “too nice”, or as “pushovers”, as they will often find themselves acquiescing to the needs of others at their own expense.