You first need to look into the requirements to bring a rabbit from the UK to the US. I know Canada has a quaraentine period due do some diseases rabbits can get there but not here. Having the required vaccinations is probably a must and you may have to keep her away from other rabbits for a certain period.
Most airlines don't allow pets, especially rabbits in the cabin. For those that do, they might not allow it for some fights due to the distacne or requirements of the country. This is something you need to check out and plan for. If she does have to be in cargo, get a larger carrier so you can add a litter box and give her some room to move around. The carriers that fit under the seat tend to be quite small, so could be uncomfortable for such a long trip.
You will need to get her vet checked before the flight. Many airlines do require a health certificate within 10 days of travel. The import laws might require vet paper work as well.
Assuming that everything clears and you can take her without too much trouble, you need to think about when you actually get there. Taking a big cage is not really an option and will be quite expensive. You can get a folding tent for short term use until you can find a suitable cage. You probably won't be able to take pellets or hay with you, so you might want to put her on pellets you can get in the US to make the transition easier. Try to find a local pet store so you can get supplies right away. Finding a vet is also a good idea just in case, you never know when you might need one and don't want to be scrambling to find one in an emergency.
Talk with your room mates to see if they can help you out with a cage and supplies, at least until you can get your own. They might have an extra cage or pen you could borrow.
I would not recommend trying to bond her and the male. You don't know how long you will be living with these people. Bonding the rabbit and then separating them is not a good idea. Rabbits do form deep bonds and do grieve loss. I am sure you would want to keep Snowy and your room mate would want to keep her rabbit. If they are not spayed or neutered, that can lead to problems and fights, if both are intact they can and usually will breed.
You do need to consider her as well. Some rabbits just don't travel well. This could mean she stops eating and needs vet care. If it becomes serious, she could die from it. For a rabbit that does travel well, it can turn out ok. Some medical conditions could be aggravated by the pressure changes. You know her best, so should be able to make the decision that is best for her and not just what you want.
