Lewis I don't think it's about whether a man would look at you twice or just about physical appearances.
My exH was overweight. Now I will admit, I didn't find it attractive. I didn't like the way it felt, I didn't like the fact that there was a huge belly I had to lean over to hug him, I didn't think he looked as good as he could do in the clothes that he wore.
So yes, there was a physical unattractiveness about it.
But that wasn't what I found 'unattractive' in a 'for the rest of my life' sense.
What was unattractive about my exH, was the unhealthiness of it all. The need to stand in the kitchen and just stuff food into his mouth indiscrimintately was unattractive; the fact he became out of breath at any physical exertion was unattractive; the inability to do simple things (tie a shoelace/get up off the floor) without support of some means was not attractive; the pre-diabetic symptoms; the constant stream of junk food in addition to proper healthy meals; the many other health problems that his (also overweight) mother suffered from that he was started to show signs of in his 30s... these were all far more unattractive and had a greater negative impact on my life than how he looked.
'Morbidly obsese' is unattractive, not because people are shallow (although some people are) but because it limits life in someway. Either in terms of duration because of associated health risks or practically because somethings are just difficult to do.
I want to be the best version of me that I can be. Now I'm not thin, I'm curvy and 'soft' and I'm definitely carrying an extra stone or two, but physically, I think that is the best version of me. I've been 2 stone lighter than I am currently, and I've been 2 stone heavier. I think I'm physically more attractive now, but I'm also fitter than I was at 2 stone heavier and I don't tire, my knees don't hurt from walking upstairs, I don't make "urgh" noises when I hoist myself up from the floor - and none of those are attractive characteristics!