I don't have any cis-gender friends from before I transitioned. Somewhere along the way they all disappeared.
My best friend from before I transitioned could not cope with it when I told him I was trans. He literally cut me out of his life completely and immediately. It really hurt because we were really close pals, and shared so much time together and travelled the country extensively together. So if your cis-friends stay by your side when you transition, then you are very lucky. Of course the dynamic will change, your male friends are now treating you as a female, and vice-versa. That's the way of the world mostly.
My family treat me differently since I transitioned. They have been very accepting and supportive, and I am very very lucky for that. But my brother and I are not so close any more, and I know (because my mom has told me) that he struggled a great deal with 'losing' his older brother. He never shows this, but we just aren't as close now, it is a shame but what can I do?
My parents treat me differently too. My dad is much more protective, never swears around me, but we are still very close. My mom now expects me to be much more like her and take on the gender specific roles that she abides by. We always struggled before, but now we get on much better and regularly go shopping and chat, it's great really.
Bottom line, most trans people appear (to observing cis-gender folk) to change much more than we think we've changed. And to them, it's a big change, often a really big change, so they will mostly treat us differently.
As long as they are not nasty, then that is really all you can hope for.
I actually prefer the people who don't know my past, and only know me as I am now. Those friendships are important because I can be my authentic self with them, and there's no baggage from my past, lurking away in the background.