Speaking from a female point of view, Its took several tries for my (Boyfriend) at the time in 2014 to get me to play, He started a fresh account with me, and 3 years later we got engaged and married. As Noppera stated it is sentimental and it feels like you form your own bubble with each other in it which is soo cute. And it feels safe. I never was a hardcore gamer but honestly experiencing it and still am, that we learnt a lot more together such as teamwork and learning to also depend on one another as we are both introverts, I remember following him around as we did the quests together because I had no idea what was happening lol, I love remembering it, haha, Later on, we built a clan together and a Raiding team, and now we're both tanks for higher tier bossing while we coordinate together. Were Still going strong ^.^

I would honestly recommend starting fresh with her, Because having someone who is higher level than her stringing along will probably make her feel like shes holding you back. And you dont want her to feel that way. I mean its entirely your choice what you do, I just felt the need to state my opinion on this subject :)

I hope you both enjoy the new adventure together! And I hope you make awesome memories as I have. I wish you the best of luck!

Peace out :)