I would accept what he says; if he believes he loves you then he believes he loves you. Whether it is possible to feel what he feels or what it means, etc. is not possible for another to know because we are not him.

I would be concerned that he has not come to see you or get to know you in person in two years though? I know he probably has "logical"/practical reasons for not doing so but you have your reasons why you have not pursued an in-person relationship either and that you are worried about your weight and being a disappointment and think you can "hold" him/keep him from "leaving" by such physical means, after nearly 20 years of marriage, when my husband asked for a divorce, my husband's ex-wife changed her hair style, thought that would help. . .

I would think about if I want another person who is content to fall in love with me over the Internet. I know it is safe and controlled but do I want to live my life that way? It is a fantasy of sorts and the other person has the same sort of thing going and is reinforcing it with you; you cannot take chances and grow and find "real"/in-person friends from behind a computer screen?