My husband has a (male) friend who is usually lovely most of the time, I get on well with him as do the kids and our wider friendship group. This friend is also very obese, probably 32-34 stone and this causes them multiple difficulties (causing knee damage, they get out of breath even walking on flat ground, they have to buy two seats on an aeroplane, won't get in some people's cars as they say they are too small, has to be picky about which chairs they sit on in bars and restaurants, etc.).
Next October one of my husbands friends is getting married abroad, some of the friends are going for a week or more to make it a full holiday, my husband, this friend and a few others are going to fly out the day before the wedding and fly back the day after. We were all talking about the trip and the large friend was saying that they would like to go for longer, but didn't think they would cope with the heat (38-40c) because of their size, they were also going to struggle on the plane because of their size, as well as doing things out there and they would like to try and lose weight before they go (for balance five years ago they went from 25 stone down to 12 stone in less than twelve months by following a medically controlled diet. They stayed at 12-13 stone until November last year then went all the way up to 32+ stone between the end of last year and now, so they can lose weight when they want to). My husband said "Well if you want to then go for it", the large friend then got really angry, accusing my husband of calling him fat, when another friend pointed out that all he had done was agree with the large friend he had a go at them as well, went silent for two minutes, then started saying "When are we going to order lunch", "Why are we waiting so long to order lunch" and other similar comments, when we all ordered he ordered two main meals and a side.
After we were home I asked my husband and he said this is a regular pattern of behaviour, the friend will complain about his weight, express a desire to lose weight. If my husband or another friend agrees then the large friend will verbally attack them, if they disagree he will verbally attack them, if they make no comment or change the subject he will verbally attack them. The large friend is normally a lovely man and this behaviour is driving a wedge between him and my husband and other friends. They have all tried in various ways to say that they are there and supportive, they never bring up his weight and will only comment if the large friend brings it up, and only in a supportive way.
I guess I am just looking for ways that they could potentially find a way to not make this an issue and help the large friend see that no one is saying anything unless he brings it up and are then only being supportive, so it should not drive a wedge between them all.