How much light does your
Chinese Evergreen (Aglaonema 'Lady Valentine') receive? It's normal for plants to lean in the direction of the nearest light source. You can either rotate it on a regular basis so that it gets even amounts of light on all sides, or you can indeed prune it back and root the top cutting for an additional plant. New growth will slowly emerge on the pruned stem of the original plant, just below the pruning cut.
I have a few Aglaonema plants and a couple of them seem to want to grow tall and lanky, whereas others seem to have a more prostrate growth habit.
The pink plant at the back left in the above photo was getting tall and lanky and recently got knocked over and the main stem broke right off. I stuck it in a terrarium that I use for rooting plants. There was already a stem rooting in there that I'd pruned off awhile back. Both of these have roots but I haven't potted them up. I probably should have cut the stems in half rather than stick them in soil as is because they are still tall. I may eventually get around to cutting the tops off at some point and rooting them too.
This is the original plant showing the emerging growth just below where the stem broke off:
