I get a lot more talkative, but I am more prone to depression, especially the day after. That might have to do with the way alcohol interacts with the medications I take. I don’t like how alcohol makes me feel (or how it tastes), so I drink very rarely.
This website explains what alcohol chemically does in your brain a bit:
Different neurotransmitters have different effects in the brain. For example, serotonin is connected with mood. People suffering from clinical depression tend to have a shortage of serotonin in their brains, and medications like Prozac can help to alleviate depression by increasing the availability of serotonin in the brain. Endorphins are a class of neurotransmitters which act as the brain’s natural painkillers.
Alcohol is a fat soluble molecule. Fats (called lipids) are a major component of all cell membranes, including the cell membranes of neurons. Alcohol enters the cell membranes of neurons and changes their properties. Receptors are located on cell membranes and this means that receptor properties are altered by the presence of alcohol. Cell membranes also control the release of neurotransmitters and this means that the release of neurotransmitters is also affected by the presence of alcohol.
So, basically, when you drink alcohol, it changes the properties of the neurons that provide you with mood-related chemicals like serotonin, which can easily make you depressed. It seems that the brain chemistry of a person will effect how you act and feel when you are drunk.