Gilly, you will get used to it. Expats seem to be more assertive / confident / arrogant / opinionated (delete as you wish) than average. We don't argue about much (except gweilo men and asian women, money and investments, bankers, pollution, is HK racist, rich and poor, religion, politics, the weather, etc. etc.) but mostly this is a friendly place.
Hope you enjoy your time here and meet the man of your dreams rather than your nightmares. As someone else said you will meet up with people that you are comfortable with, there are all types here. I don't meet up with many expats because basically I have little in common with them but have a very happy life with people I can connect with. I am sure you will be able to do the same.
Last point: age is not the issue, it is the person within. I can have deep and meaningfuls with someone who is 10, 20, 30...60, 90 as long as they are open and thoughtful people. If they are shallow people or unwilling to be honest with themselves then it does not matter what age they are. It is the ability of two people to connect at a deep level (be they just friends or partners) that matters. My first wife was 5 years older than me, my second wife 24 years younger. No difference that I can see created by the age, but cultural differences are another thing.