This weight thing, among other items, is concerning. Have you checked any weight tables? Sure charts are charts but they are based in science. I looked at several and the very low end among them is 125 pounds. So you were off the charts for awhile but are now just inside the low end for height and age. BTW 154 is the top end for average and healthy. What you "feel" may not be healthy for you. You'd be much better off addressing why you feel this way rather than changing the weight.
As for the R with NG, are you really ready to be in an R with anyone? You might be helping everyone involved dodge a bullet here. I/we here cannot know what's really going on with him and with you but from what you write it seems more like not being ready for an R. A huge fight about asking a JW for directions in the airport? I'd find that hilarious if I did it. But I have huge confidence and ability to laugh at myself. In fact I'd likely bring it up for years... "Remember the time I asked a JH for directions in the airport? OMG, bah ha ha. That was so funny. I was such a moron that day." Or something like that. That's just me but why take it so personally? Almost seems like a self-esteem issue. Of course if NG is using it to put you down amd build himself up, that too is a S-E issue but for Him!
Perhaps rather than break it off fully, perhaps just take a break from him? Decide if you are ready to date and be in an R. Just at least explore if all that's going on is not as much about you as it is him. I don't at all say these things to be mean - just to be honest and give you another view. I hope you see it that way.
DonH Midwest Me 56 WAW-EXW 55 Met 11/95 / Married 5/00 Bomb 6/20/05 / She Filed on 6/2/06 / Divorced on 10/9/06 4 who'd qualify as GF since D & dated about 25 women since D