It's not absolutely necessary that you speak Danish to live in Denmark, but it will make life so much easier for you if you do and also language school is free for the first 3 years.
Things to consider:
- Not all of the older generation in Denmark speak English and a few of the younger generation do not speak it that well. When my husband first moved here, I had to go everywhere with him (to the doctor, the car dealership, the kommune, the bank etc.) to ensure that there were no misunderstandings because of communication. Granted, there were times where he and the person he spoke to managed fine on their own, but there were a few cases where I had to translate everything and the most common situation would be me intervening here and then.
- Danish is the official language of Denmark. There are no official second languages. Some places will issue documents in English, but usually only if you ask for it specifically. Otherwise 100% of all the paperwork you receive will be in Danish.
- It is much easier to find a job in Denmark if you speak Danish. Much, much easier.
So, basically, learning how to speak Danish will make your life easier, and it will make you less dependant on your boyfriend. It might seem like a little thing now, but I have lived abroad and I know just how rotten it can make you feel when you cannot do simple things like make an appointment with the doctor, ask for a specific item at a store etc. without having to worry about being understood or, even worse, needing help for it. Once I spoke the language well enough to communicate, I felt a huge sense of accomplishment and much more independant and more settled in my new country.
Also, there's the whole attitude issue. There are a small group of expats in Denmark, who hate everything about it here and a few of them refuse to either speak Danish and learn how to speak Danish. This does not go over well with the Danes - and as a Dane and a former expat, I cannot really say that I blame them. Imagine someone moved to your country and refused to learn the language there. It is one thing not to speak the language the first years or so after moving here or not speaking it well - as long as you're trying. It's another thing entirely to not want to learn or refuse to speak the official language of a country, but instead insist that everyone around you make an effort to speak English to you.
Learning the language of a country is important for a successful integration.
As for the negative expat bunch over here. If you should stumble upon them, my advice would be to avoid them. I am not saying Denmark is perfect or that expats should not feel free to rant and rave - I certainly did my fair share of ranting when I lived abroad and I'm ranting and raving now that I've moved back, but these are in a different league all together - and I have seen them make other expats who were otherwise happy to live here, quite unhappy and suddenly refusing to speak Danish or have Danish friends, because they became influenced by all the negativity.
There is a huge group of friendly, funny expats here, so if you decide to move here, my advice would be to hook up with these, adopt your boyfriend's Danish friends and have these friends introduce you to other friends.
Danish, have lived abroad for several years and recently moved back to Denmark with my non-Danish husband.