This sentence basically means that the speaker and the listener have not had the opportunity to experience a significant amount of time together. Without the context, it is hard to detail it more than that. The part "...haven't really had..." is actually somewhat vague as "really" in this context is defined by a collection of experiences that someone just reading the sentence can't infer. If the conversation were between a boyfriend and girlfriend who were discussing the possibility of living together it would be interpreted differently than a husband and wife with children who were talking about travelling to see the world for example. The sentence shouldn't really be taken completely literally though as it does not specifically refer to living in the same residence. Think of this sentence as refering more to the experiences shared between the speaker and listener in their lives rather than a specific time frame.

Hi! Actually it depends on the context [emoji] But in general - it means simply what it is - you hadn't yet had a chance to live together)))