If you enjoy running, I would keep it up. Don't worry about speed so much. The great thing about running is that you can have different goals than just being fast or coming in first. Some people have a goal of just finishing a race. Some people are there to just beat their last time.
The other thing is running everyday is not what will necessarily make you faster. You need to do speed drills in addition to your normal runs. People will always be faster. There are some real beast out there!! Remember, it is about you becoming a healthier you. I saw this t-shirt that says "You may be slow, but you are lapping everyone on the couch!"
One thing that is nice about running is that you can schedule races (5K,10K, etc) every 3 months or so and that will give you the incentive to keep up your running and losing/maintaining your weight. There will always be "walkers" at these races, so you can be faster than them!! The other thing is while you are getting/staying fit, you will also be donating to a worthy charity!!
I wish you much success!!