I need travel, with my wife from Beihai to Haikou

Then we will be on to Sania area at the end of our 3 week honeymoon to China.
We are going to Beihai from Nanning and then for some beach time
Can I get easily to the ferry port ... how long do I need for the journey, and can I get a bullet train to Sanya, or a conventional train.
I would like as much information as I can get from RECENT travelers, to smooth our way.
Any info, even if its duplicated would be so very welcome.
Thanks