As hard as a split would be, I do think that in time it will help Elaine.
I do not wish bad on her, not at all, but I think the last ten years speaks volumes. They are at different stages of their life and Elaine has been with Neil since she were a teenager. She needs time to live her life, meet someone who she is compatible with and who can make her happy. Her weight issues clearly mean that she is overeating, and this could be her way of coping with the general unhappiness in her life.
If she leaves Neil, it will hurt - but she will find herself and maybe her life will change for the better.