I don't keep track of my strength stats (and I don't do traditional weight lifting to gain strength), but I was, before I had children, athletic and strong. I could keep up with most men my age in most sports. About 7 months ago, when I had trouble getting off the ground after playing with my 4 year old (20 lb overweight), I decided I needed to get back at it. I could go 20 minutes with a personal trainer before I felt like I was going to pass out. It took me 2 months before I could go the full hour and feel good.
Now, I can do about 20 push ups (pre workout), I lose count on my sit ups, and I run 8 k at a speed of 6 without feeling out of breath. I don't think I'll ever be where I was at before kids again (I just don't have the time), but I feel good and I can keep up with my kids!
Don't worry, keep working at it, set small goals, and before you know it you will be where you were several years ago!