Hi Anastasia.
Like as has been said before the wearing of a bra or not is not a big problem. Yes, Thais are far more conservative than we westerners and in the touristy areas they accept we have a different approach to life. Just be a little sensitive to thier cultural beliefs and if you don’t want to wear a bra then don’t wear a flimsy see through top.
Now as regards showing affection to your patner/spouse the Thais just don’t do this. You will rarely see a Thai couple holding hands let alone hugging and kissing. This is not just adult to adult but I have noticed a lack of affection shown to children over the age of about 7 from their parents or family members. This lack of showing affection can be seen as soon as you fly into Bangkok. Thai people do not greet family members or friends they have not seen for some time with a hug anda kiss on the cheek as we westerners tend to do. There is no physical contact, just a smile and a wai. Now again in the tourist areas and Islands, holding hands/hugging and quick kisses in public are regarded as the westerners normal way of doing things and accepted. Not so much in the more rural parts of Thailand but they are getting used to seeing it slowly with more westerners living in their midst.
Maybe this way of theirs not showing affection in public stems to when the family chose your spouse for you. Nothing to do about love. Then when you are married you lived in the same house as your parents and siblings and all of you go to sleep together on the floor in the same room. Can’t really get romantic like this. This still happens in some more rural villages but much less so.
Thailand is a lovely country. I am married to a Thai National and have lived in a small village in Isaan for three years. I still learn all the time about their customs and cultures. Some extraodinary, unbelievable, quaint and some riduculous. But as is often heard said here by westerners TOT (This Is Thailand)
This article and it’s posts are very informative and if you can remember most of what has been written I am sure your boyfriendand yourself will have an even better time here on holiday.
Just remember Thailand is still light years behind most Western countries.
Other things I suggest you be aware off is the corrupt police here. Not the odd policeman but the majority. Just be careful definetely no drugs of any kind, very severe penalties if caught.
Next advice. Thailand is a cheap place to buy things but there is a reason for this. Generally the quality is poor especially in regards to clothes and shoes. You can buy a copy opf just about anything here in Thailand, but!!!!!!!