Big deal if your body is "not what it used to be." You said you aren't overweight. Are you healthy? If you are healthy, that's ALL that matters. Too many of us are overly concerned about our outside wrapping. It means LITTLE in the scheme of things IF we have our priorities straight.
If you are healthy, NOTHING else should matter. As you age (especially after having children) you will NEVER have the same body you once did. That's called life. All things change in life and sadly, all things droop a little:) ...unless of course you're into the new PLASTIC image women want so much and will pay for it!
Enjoy your family, your health and thank God every day for what you DO have. God bless. Summer is MUCH more than bikini's. It's FAMILY TIME!