It won't make you sick. Wine is a natural antiseptic because of the alcohol content. And alcohol is used to get rid of germs - I have recently been diagnosed with high blood pressure and need to go for regular blood tests to see how well the medication is working, and what gets rubbed on my arm before the phlebotomist inserts the needle is some strong alcohol. So of course there won't be any mould - the alcohol will kill it.
And it will still be alcoholic.
It just probably won't taste nice. Once the bottle is opened, air gets in and oxidation starts pretty fast. You can taste the difference the day after. This is why there are devices such as Vacuvin - I have one and the idea is it will pump as much air as you can out of the bottle, but it's not entirely successful.
I tend to only want wine if I need it for a recipe, and I love wine boxes. You get a cardboard box with a thick plastic bag inside containing 3 bottles of wine, and there is a tap on the side (bit of a fiddle at first to get it out of the box - just follow the instructions on the box). Squirt wine out of the tap, and as you do that, the bag shrinks down so no air can get in. The wine will last a few months that way.