Richard Rider has had quite a mixed love life since the character was first introduced in 1976 in Nova 1.
His first love was school sweetheart Ginger Jaye - it was more a close friends than actual lovers. Ginger eventually married and moved on. Nova's second date was Laura Durnham (New Warriors) a grad student from ESU. Although Richard was also falling in love with fellow teammate, Namorita which out of all his relationships is considered to be the one that most readers are familiar with.
Nova essentially blew his love life with Nita - becoming just partners. During Annihilation Nova/Rich had a relationship with Gamora, the deadlist woman in the Galaxy which lasted until Gamora walked out of the United Front. Later, after Gamora was cured of being one of Ultron's Selects, Gamora rekindled her relationship with Rich up until War of Kings.
Recently, Nita - having died at the Stamford Incident (Civil War) was brought forward in time by Nova's life long foe The Sphinx. Nita managed to survive the battle and ended up rekindling her love affair with an older Richard Rider up until Nova apparently died during the climax of the Thanos Imperative.
Daz/ Nova Prime Group