It depends on the apocalyptic event happening. If the same event happens as in Y: the Last Man, then statistically speaking it's highly unlikely for me to be the last man.

But for the sake of this thread, let's assume I have survived the apocalyptic event, and I have to now make it through the after effects. Since the apocalyptic event itself is important, lets just say that an until now dormant disease wipes out humanity in a very rapid fashion and I'm one of the few immune to it. As a result, I'm basically on my own.

I figure that almost immediately we will lose electricity, water, and gas. I will likely lock myself up in my apartment until I am forced to come out because I've run out of supplies. The fear of getting the disease myself may mean that by this point I will already be very hungry and thirsty. However, before breaking and entering I will try to look for others. There are bound to be government officials going around, right? Guess not.

I won't be able to break into other buildings. I simply don't know how. I can try to break open doors, but I'm likely to fail. There are a lot of 24/7 stores here, but they will probably close when some strange disease rapidly spreads and kills the population. I can try to break through some windows, but I'll likely get wounded in the process and if they are double glass I might even fail at that. By now desperation is sinking in. I'm weak, alone, hungry, thirsty, and out of toilet paper. I will search around for ways to get supplies, but likely my only option is to rob a convenience store. If I do not succeed at that, I will simply die. If I do, then I will probably be wounded in the process.

Either way, it is prolonging the inevitable. I will get food and drink, but I won't get a warm meal unless I manage to build a stable fire (which is surprisingly difficult if you've never done that before). Fresh food will not last very long, and I will eventually have to go to different convenience stores. At that point, the depression starts. I have no clue whether there are others. There must be, but how do I reach them? For all intents and purposes I am completely alone. My parents died, my girlfriend died, my friends died, so pretty much everyone I ever cared for is dead.

I'm too stubborn to kill myself, but depression doesn't always make you want to kill yourself. You just stop caring about your wellbeing. If that happens, it won't take long before I get ill and will eventually succumb to starvation and dehydration.

A pretty boring death, really.