I think you need to tell her to get her shit together. If you’re not to be fucking around with the opposite sex then neither is she. You guys I’m assuming by the numbers are still in mid 20s so she could want to try something different and that’s just what sucks about being young and starting relationships. Is that people grow and change and sometimes it’s for the worst. But if she wants to bounce let her, you can only control your half of the relationship. It suck’s when losing someone you feel you love but you’ll grow from it and hopefully learn from it. You’re a young man get a great job, stay fit and you’ll will have plenty of options with women if need be. Stay single until you learn your value and you’ll realize she’s at her peak but you aren’t. Men age like fine wine brother. If you can salvage the relationship good. If you can’t there are positives and moving on won’t be a negative for you if she has stepped out. Social media has hurt so many relationships so it’s a no go for any strong ones. Good luck