<human>: Give me the gist of the text in a nutshell

Just yesterday my girlfriend started to text me more serious than usual and started talking about the future of our relationship. Call me stupid for thinking this just out of highschool but I personally would be more than alright with spending the rest of my life with this girl and we have gone through a lot together and I can safely say I've never loved anyone this much. Just yesterday she started talking about where our relationship is going and told me that before she would want to be married she feels like she has to have sex with someone else and suggested that sometime (in the undecided future) she wants to see us taking a small break to "explore our sexualities" and then getting back together.

Is this normal? I'm not really sure what to feel with hearing this. In a way it makes me feel like I'm not enough for her (might I add we have a very sexual relationship) and the thought of it makes me feel like we wouldn't be able to get back together and she'll find someone else during this time. Is this something I shouldn't worry about until it actually happens (if it even does who knows) or should I be concerned with hearing this? Personally I don't feel the need for this possibly because both my parents have strictly only had each other as partners and both have been together since highschool as well.
<bot>: Girlfriend talking about needing to have sex with someone else before she can get married, don't know if I'm thinking too far into the future or how I should react.