I know it's often said that someone becomes an angel when they die and go to heaven, and perhaps this is what your aunt meant. However, this isn't exactly what the Bible teaches.
It says instead that after we enter heaven we become even greater than the angels. One reason is because God will give us (and not the angels) the authority to rule over His creation–something we can only barely imagine right now. The Bible says, "It is not to angels that he has subjected the world to come" (Hebrews 2:5). It also says, "Do you not know that the saints will judge the world?" (1 Corinthians 6:2).
Can those who are now in heaven see what's happening on earth? The Bible isn't completely clear about this, although some Bible scholars suggest this may be the case. For example, after writing about past generations who are now in God's presence, the author of Hebrews says, "Therefore, since we are surrounded by such a great cloud of witnesses ... let us run with perseverance the race marked out for us" (Hebrews 12:1).
Never lose sight of the fact that this world is not our final home, but we were created for eternity. Are you certain that you will go to be with God in heaven when you die? You can be, by giving your life to Jesus Christ.