Can NC still work after 5 months separated?

Apologies let me elaborate my girlfriend and I have been together for close on 5 years after meeting at work, close on 5 months ago we separated my girlfriend sighting constant external pressures courtesy of my parents none acceptance of her, you see I was previously married and have 2 children and my parents carried much animosity towards my girlfriend thinking she was in some way responsible for my marriage breaking down. You see we have quiet an age gap I’m 39 she’s 25 and this also had met early resistance from both sides of our family’s. We also were only 7 months ago going through IVF and obviously planning to start a family, after 2 devastating failures my girlfriend became overwhelmed and moved back to her mums, I obviously thought this would be a short term thing given the amount of medication required I knew her hormones were also all over the place, we were both emotionally shot but I expected things to settle, eventually she wanted too return after a couple of weeks but I resisted as I was hurt that she’d left home at such a sensitive time, she remained at her mums for another month and it was at that point that I began trying to convince her to come home, she said that she no longer wanted to be with me that the relationship carried to much baggage, it was at this point that I panicked I didn’t want to lose her she’s the love of my life we were doing IVF 3 months earlier so I became desperate needy I was making all the classic errors she asked for space and I pushed harder for her to come home all up I think it’s been around 6 weeks that I’ve really persued her to come home, finally after finding this website earlier this week I apologised for all of my behaviour and she was happy to accept but I’ve since learnt she’s been on a date and when I confronted her she said we’d been separated 5 months and she could do what she liked, I know this is a complicated story but I would appreciate If anyone could offer feedback on whether I can still apply NC? You can imagine my panic upon learning of the date I don’t want to lose her please help

Hi all I’m really keen to hear some feedback on my post, I’d really appreciate some outside input thanks everyone