This is a tough call - would you as a man, think a Fattie5.5 is going to change into a HB 6.5 just because she is 'confident'??
Women call men who approached that look fugly to her as a 'creep'. Granted, women are slightly more forgiving in a man's looks, but are still shallow b!tches if you expect to keep her in the long run.
I think a man must come to realize and ACCEPT what level of attractiveness in a woman he can pull CONSISTENTLY. If you keep failing, then accept you are not good looking enough and lower your standards. There are lots of fantasy talk amonst nerds here trying to brainwash the realistic with idealistic that other things are going to replace looks.
Rarely unless you are famous, rich, or LUCKY (being at the right place at the right time), you are going to have to accept Darwinism and survival of the hottest wins.
Lastly, for an effective and longer lasting LTR - look beyond sex and looks, and get to know the woman more so you don't waste your time in life.
Be well
Exodus