It's always hard and to keep long lasting friendships. Good thumb of the rule is that you cannot force it and it cannot happen over the night so it is best to go with the flow. If you are in a new environment, it's best to be pro-active and seek out your hobbies and interests. Go out and about, try to mingle. Internet is the common medium these days to do all sorts of communication, and one advice is to use maybe a meetup.com up and seek some common interests. It's hard and you really need to make an effort, comfort zone is somwhere you cannot be.
I like being with guys, but I will get bored of sex when a few months later. I do not know what to do. I still like the guy, more like brother type… Is it common?