Am I being left behind? in 30 Something ....

Ever look around you at people involved in your life and think..... how did they get there and me get here. Although my life is bloody good, don’t get me wrong. I have a wonderful husband a home I am proud of (I would like to own my own but hey another day maybe) a wonderful family who I adore and a job I am good at. But why am I not getting pregnant, have loads of disposable cash. What really annoys me is I know people who don’t and haven’t worked a day in their lives yet the state gives them all sorts of money and I am not struggling so much but just keeping me head above water. How is that fair? As for the getting pregnant thing.... that’s a whole other ball game. My hubby doesn’t have a great sex drive, he suffers with back problems etc but I am worried that he doesn’t find me attractive, yes I have asked and he says all the right things. But let’s be honest here… I can’t blame him. I’ve put on a lot of weight and don’t like myself. I really want to initiate sex but my confidence is at an all time low. Any help or suggestions would really help?! Sex is so few and far between and I know I need to do something about it but what and how when I feel like I am not sexy? Any suggestions on ways to improve self confidence. As a teacher I teach children to be confident but can’t seem to transfer those skills to myself ..... help!!!