Let me try shorter sentences at first, then a longer one.
Take the grace known as "the communion of saints".
This gift - this help - from God is one way of having "intimacy" with God and everyone who by grace is in communion with God.
Death can't separate the children of God.  Death has no power over God and those in union with Him. 

So having a lively and intimate interior life with God means that DEATH increases the intimacy we have with these people who have died because these people are now TOTALLY united with God - they have the beatific vision - whereas our union with God remains an imperfect one, diluted by our own fallen state (prone to self-focus, lusts of various sorts, etc.). 

So we can - through God - talk to these people, ask these people to obtain grace for us - tell them we're sorry for having upset them at some point during their life here on earth.   So we can be sure that God allows this greater intimacy with these people BECAUSE HE WANTS union and intimacy!