I just got a new job, but THEN the opportunity of a lifetime came along. Please give advice?

Hi all,

I've been a freelancer for the past two years. About two weeks ago, a client of mine that I've worked for for 9 months offered me a full-time job. Excited to be a part of a team again, I tentatlvely accepted. It's a great company, great benefits, and a very strong presence in the area where I live.

I've been working there full time for JUST A WEEK NOW. In my first week of working, my husband's job offered him the opportunity to be relocated to London for 6mo-1yr. We both feel its the opportunity of a lifetime, but I feel guilty and anxious for going back on my word a week in. Thoughts?