Hi!
I was exactly in your situation.The fist suggestion is to not stress too much! Because I stress so much without the need that I am already in my second day of migraine.
In my situation, I got here to be with my boyfriend. I am American and my boyfriend is Ukrainian. He got one year contract with an university for his post doctoral fellowship.
So we plan to stay together in Germany while he works so what o do?
- First I got a
health insurance by a German company, I pay a whole year for it as it was very cheap. This was before leaving as it also had travel coverage for baggage lost etc, just in case something go wrong during the trip.
-Arrive to Germany as a tourist
-Register in the city we plan to stay and got this registration paper.
- Went to the city office to get the appointment for the resident permit- this day they give me the appointment date ( 2 weeks after) and what we are going to need. In the paper they put 8:30 am first appointment and then at 9 another appointment, in different rooms.
From fiancee they will require:
* 50 euro
* city registration paper
* photo
* health insurance evidence ( just a copy of a paper that you are insured)
* Application form ( you can get it in the office that day)
* Passport
My boyfriend needs to bring
* University contract where it says how much he earns ( to calculate if he can support me)
* Apartment contract
* Gas and energy bill
*Passport
- The appointment day!!! (yesterday)
- First appointment 8:30 - So here they calculate if you can support her using your bills, apartment contract and salary. In our case they also ask for a paper stating the net earnings, we still don't have it so the lady said it was okay just to provide the brute amount. She will ask for passports and will make some papers in the computer. This takes like 15 minutes because they need to make photocopies etc. Then she refer us to the other office and she hand in the papers herself to the other official. At this point we have just sing this papers staying that everything written was correct. This official was kind and speak English. Funny thing the only thing I have said until this point was at the end DANKE and Shuss.

- Second appointment 9:00 am - The official ask for my passport, photo, health insurance evidence and residents permit application. The lady was even kind enough to clarify a part were I have a doubt in the application. Then she print the resident permit and put it on my passport. And that was it!!!
So the only words I said on the 30 minutes I was there were Danke and Shuss.
I was in shock and still in shock, that it was so easy process smooth and organize. So nice officials. I was expecting for sure they will tell us to bring other documents or papers but not in my case.
The funny thing is that when my boyfriend got to change his visa from student to employee (he has done his phd in Germany and is already his 4 year here) it was a very different case. Even tho he had all the papers require, contract, letters from bosses, from university, it took him almost a month to get it!! They where like playing with him, telling every time to come back with another letter. He told me they read every paper and everything on his application. In my case they don't even read the application!! They don't ask for the registration paper!! He says all the time making fun that is just because his Ukrainian passport.

,
My wishes are that you and your fiancee get to have the same experience as I had!!