The hole wasn't deep enough. You needed a hole the same size as the tree. Put the tree in and push it down as far as you can with your foot and cover it with soil. Go to a gardening store and buy a tree that you like that is outside of the store and plant it the normal way.
Plants that are not normally "houseplants" may not be kept indoors over winter unless they owner has special skills and/or conditions that accommodate the special needs of such plants. All others will kill the plant. Commercial morons who sell evergreens like Cypress and Junipers as Christmasy plants do so because these plants can be dead a month and still be green. By the time the purchaser figures out that their cute little tree is dead, it's been a couple months and they blame themselves, not the store. Those kinds of trees MUST have a quiet period outdoors just as sleep is neccessary to people. It is a period of non-growth in a period that normally has poor growing conditions, -winter. Their energy is conserved for spring growth and rejunvination. The inside of a home is much too dry, -like a dark desert to these kinds of plants. Even if watered just right, they still don't get enough light. Now, you know.
