ive been on my own a couple times, went on my own for my first trip. ended up having a year out there on me own 2010.
aslong as you are responsible you will be fine.
its all the idiotic plebs that end up in bother.
the thai people are fantastic, Thailand is known as the land of smiles for a reason.
its a great place to go too. I find Bangkok VERY busy tho. maybe a little too much at times. I tend to stay there for a night or 2 after arriving and then move on.
koh samui is a much quieter than Bangkok.. still lots to do and plenty of people about but nothing like Bangkok.
Pattaya is always fairly busy and you get a bit of everything there. there are around 10,000 bars in Pattaya and there is a great mix of people from all around the world. its an interesting place to say the least!
Phuket is much more for the couples I would say, a lot more chilled out than pattaya and Bangkok. Phuket is also full of Aussies as they can fly directly in.
theres a very quick account of how I find Thailand anyways..