As far as with sex....you can have sex normally. Its actually quite healthy as it help balance her raging hormones. Sex further along in her pregnancy is also good because it can cause her to go into labor on time. All the huff and puff about dangers, there really are none; UNLESS she has early complications (which even still shouldn't affect your sex life).
So no worries, you can continue to have sex normally, and it may be good to look up pregnancy sex positions since the farther along she gets, the harder some positions will become.
Congratulations on your pregnancy, and I wish you both the best. I hope this helped