Visa for fiance traveling with chinese citizen, both living in US

My fiancee and I wish to visit her residence in China. What kind of Visa should I apply for? If I say I'm a tourist I need hotel reservations. If I say I'm visiting friends I need a letter of invitation from someone in China. My fiancee (Chinese Citizen) lives here with me. Can I have her write the letter of invitation for me?

Please help me with this confusing situation

Gary/Goldenruwl