Also, consider a psychiatric hypnotist. He can put you under and ask you to recall the memories of your younger children, and then ask you to recall your teenage years. If those memories are intact, he can record them and play them back for you, or if your memory loss is from a traumatic incident, he can help you absorb them over time and accept them.
As for being forgetful whilst talking, concentration may be goofed up from stress or illness or lack of sleep. Poor sleep can also be why you don't remember parts of your younger life. So, you could also have a sleep test done to determine if you have sleep apnea.
Hi.
Memory loss can be caused by many conditions, including psychological stress, trauma, brain injuries, some neurological conditions, etc.
You should consult a neurologist to properly assess your symptoms and to determine whether an organic cause of the memory loss can be identified and treated.
Good luck.