In yesterday's gospel reading Jesus was speaking about the vine and the branches, and in tomorrow's he will refer to the fruit that we are to bear.  This context explains a good deal of what Jesus is trying to say today.

To paraphrase what he says, in a first movement the Father loves the Son, the Son lives in the Father and keeps his commandments, and the Son's joy is complete.  The opposite is also true: the Son loves the Father, the Father lives in the Son and keeps his commandments (very similar to the meaning behind "Whatsoever you shall bind on earth..."), and the Father's joy is complete.

In a second movement, Jesus says that our relationship with him should be the same: the Son loves us, we live in the Son and should keep his commandments (which he will reveal tomorrow as our need to love one another), and our joy should be complete.  And, of course, reciprocally we should love the Son, the Son should live in us and keep our commandments, and his joy should become complete.

This relationship between the Son and us is not as tight and pure as it is between the Father and the Son and is filled with a great deal of "shoulds."  It is, at least at present, very mitigated: when we get closer to living as the Father wishes, our desires ("commandments") will be just what the Father and Jesus already wish and the way that we live will complete their joy (well, God's joy is already complete, looking at it from the viewpoint of God's nature, but this is what we see as God's response to our living his life).

The Father and the Son (and the Spirit) are already in perfect harmony and share perfect bliss in each other.  We are and always will be on the Way (we hope) that leads to the heart of their love, but we need to start now to enter into that mystery by our desires, our choices, and our acts, the fruits of our being truly rooted in Christ.