@harmonica,
"Women my age or older, do not talk about that point of their lives hardly, so I don't have to hear it, whenever I date someone my age or older.
So when she talks about It, I feel jealousy and insecurity. For example she is 21 and has already had four relationships. I am 36 and have only had 4. So
I feel intimidated that she has had more experience than me."
This young woman is only a few years out of high school and maybe hasn't finished college. Her most vivid memories are of the things and activities younger people share at this time in their life. I'm concerned that you worry how this age difference is perceived by others but more so that you feel jealousy and insecurity when she talks about her recent past. This may not wind up being a good relationship for you unless you can get past those obstacles.
Just also be aware that this young woman may occasionally feel out of her depth when she meets your co-workers, friends and relatives. You obviously have control over your conversations and behaviors but people tend to remark on age differences (her side and your side) you need to figure out how you and she are going to respond. Just try to remember that you were a teenager before she was born so your teen and childhood memories are going to be totally foreign to her and hers totally foreign to you. It's not fair for either of you to resent each others experiences just because they happened at different times.