I think it is a foreshowance of Christ and the Church, as if it was not good for the man to be alone (which Adam had God his Father, and the animals, but still ‘alone’), would not that also apply to Jesus. Wouldn’t Jesus also need such a companion.
Some supporting verses:
[Ephesians 1:23]
And the church is his body; it is made full and complete by Christ, who fills all things everywhere with himself
(Going on the 2 shall become one flesh theme here)
Eph 5:31 As the Scriptures say, “A man leaves his father and mother and is joined to his wife, and the two are united into one. 32 This is a great mystery, but it is an illustration of the way Christ and the church are one.