You can TOTALLY do it! You just have to have a little faith at first when you aren't seeing results that eventually they'll come so you stick to it. For me, I have to work out hard and diet for a good four weeks with no results and then all of a sudden I start to see the changes (i think in those first few weeks, I'm still losing, but probably from my boobs or my ears or some other unhelpful place!)
And get a personal cheerleader!!! Recruit your FI or a friend or someone, someone to cheer you on, ya know?
Oh - and don't totally focus on the numbers - use how you feel and how your clothes fit as a gauge for your success Good luck - you can do it!!!