I have this house plant whose bark looks zebra-like. It seems to grow from one stem with longish leaves with parallel veining. The leaves are a prety dark grean; it is only the stem, where leaves fall off that make it look zebra-like.

Wanting it to get more than one stem, and fuller leaves, I snipped off the top. The top did branch out but is now so heavy, the plant can't stand by itself. It is about 3 &1/2' tall. Anyone have any ideas what this is?