My fiancee is a hepatitis b carrier, am I going to get it too?

Probably not,vaccine. Hep b can be sexually transmitted, although more commonly it is through contaminated blood products or at birth in regions of endemic disease (far east, middle east, africa). One can get protection with a hep b vaccination (3 doses over 6 months) which appears to give lifelong immunity. If you are not immune to hep b (can check with blood test), get vaccinated; use condoms.
At risk. Hepatitis b is transmitted through blood and body fluids including saliva (kissing, sharing drinks) and semen (sex). If you received the 3 dose series of the hep b vaccine before you met your fiancé you should be protected from the disease. Your doctor can check titers to see if you are immune or have been infected. S/he can also give you the vaccine.