Some people would strongly argue that the key to success is consistency, whereas some would argue it's setting and proper situation, variables etc. I really believe that the consistent force is the winning force. The water in a river might not be stronger in any given instance than a rock at the bottom - over time the rock is worn down by the river water. Consistency is key. Rome, nor the Grand Canyon were built in a day much less a few months time so commit to an idea and start chipping at it!
If you want to lose weight, identify ways you can easily make changes to help get you consistently working towards your goal. It can be giving up soda, not getting dessert or even cutting back your portions in meals - anything you can measure and be consistent with to watch the change and progress you make.
Same can be said for strength, if you want it... WORK FOR IT. You can't just bench a few times and hop under 335 like it's light-weight, I still can't play with 335 like light-weight. Strengthen your accessory muscles and get your auxiliaries in, over time the weight gets lighter and you can handle more and more stress on your muscles.
In life, the same as true in both weight loss and fitness... Consistency is key. You can't give up when the "going gets tough" and you can't quit when a few challenges come knocking at your door. Sometimes it's your bedroom door first thing in the morning; wake up ready to approach the day like you are going to win every challenge! Try your best to succeed, accept failures as a learning lesson rather than an actual judgement and evaluation of your worth. You have to first fail in order to succeed.