Well, i think all is up to you... I mean, if you are gonna change how you look for someone, do it for yourself only. There is nice amount of people that find girls with bigger weight attractive, well its better then skin and bones on level of anorexia and even worse that used to be promoted and still is till some point promoted in fashion and modelling industry. I myself though find medium weight attractive the most.
Well anyway, i do think that you shouldnt be forced to lose weight if you dont want to. You can raise your girl to not follow your way of eating and growing with more weigh then average, even if you yourself arent average.
Whatever you decide to do, we are there for you to support you