1. Be prepared for the family. I don’t mean you, her and little Timmy/Ivan. I mean her Mom, Dad, siblings and possibly cousins. You are marrying into a family. It means frequent visits, gifts, and taking care of them when they are old. Russians look down on nursing homes. It is a broad generalization of course, but Russians are closer with their families. She will talk to her Mom a lot, if they have good or normal relationship. Skype is your friend.
2. Visits. If your significant other leaves their family in another country, prepare to let her/him go there often. Or go together. Or have family members come over and stay here weeks or a couple of months. Friends and family in Russia generally try to see each other a lot more often. Social networking does not replace real friendship or family relationship.
3. If he/she comes here they will learn your language. Try to learn some Russian, it will go a long way in helping to understand Russian mindset and culture; or when her Mom says that you are too skinny and you need another
kilogram slice of pie. Remember - feeding is caring.
4. Americans frequently call their acquaintances friends. There is a distinction between the two in Russia. Friends are friends through thick and thin. They know what is going inside your head, when you have a hungry face, a sad face or you just need a beer. They are like family. If you make a life-changing decision like moving away from them, it will require a lot more work and preparation than giving a week/month notice “oh, btw, guys I am moving to Possum Run….”
5. We still have pretty strong gender stereotypes. This is another broad generalization, but it is true. Such a simple thing as women firefighters and male nurses may seems unusual. As well as a guy, who can't use tools. All this is really weird, considering that a lot of rail road workers and painters at construction sites used to be female.
6. Penny pinching or being too frugal is not a virtue. Being greedy is one of the worst things you can be. Thrift stores, yard and garage sales might take some major adjustments. In any case you probably should not go "honey, look what I got you at a garage sale" until he/she is totally ok with the concept. Russians tend to brag more about how much they spend, when Americans about how little they spend.
7. American 8 weeks maternity leave is cruel and inhumane. If you are moving with your SO to Russia, be aware she might be off work for a couple years. She may also want to be off work for the same length of time if you live somewhere else. Men are still the providers (gender stereotypes), just be ready.
8. If you are marrying a guy, be careful how affectionate you get with other guys. He will most likely not understand. Casual affection between friends of different gender is not common in the mainstream society.
9. Russian men are more likely “to go outside and talk” than call a lawyer, law enforcement or mommy. Scores are settled person to person or family to family. Causing someone harm physical or otherwise may mean physical consequences. Cutting in line at the airport for example may result in "going outside", instead of getting complained on to airline or airport employee. Boys (and girls) are raised to be able to stand up for themselves instead of going to complain to someone.
10. American Man/Russian Woman couples are more common and last longer than Russian Man/American Woman. American women in general consider Russian guys stuck in Middle Ages or too patriarchal (gender stereotypes) and Russian guys prefer women who spend a lot more time on their body and appearance than is customary in the American society.