When should i reach out

My fa broke up with me seemingly out of no where’s. We were together for almost a year and all the time we were together was amazing. We shared so much in common was always on the same page about everything never fought or even argued. A week before the break up she started being less talkative and i tried talking to her about it and she just kept getting more stressed out and overwhelmed about how we would work out. She would say stuff like how do you know you won’t wake up and not love me or how do you know you won’t love every bit of me. I think she just got so worked up that she had to breakup so she could feel free and not be so stressed anymore. I waited a couple days to reach back out and she was completely guarded and not even herself, the only reason for the breakup she gave me was she felt like our personalities didn’t align, which was never the case for a second. I’ve since been in no contact with her for approaching 3 weeks now. I’m respecting her and giving her the space that she wanted with breaking up. I can’t dismiss the feeling of that she’s the one for me cause of all the amazing times we spent together. I desperately wanna reach out but don’t wanna ruin any chances of getting her back, but i also feel that even if she was ready to reach out she’s probably too scared to cause that’s just who she is. I’m just wondering what i should do cause i don’t want to let her just slip away if i don’t reach out but i also don’t wanna mess things up for us if i do reach out