I also sent her a text validating all her parents support over the years which I recognise I have taken for granted. I said it was a shame I now realise everything that I should have done and its all to late. She responded by saying 'yes' is all too late.
Things like this will be seen as pursuing by her and it doesn't help you to see her answer. There are some very good, considered ways to apologise if you need to that will come over as strong and meaningful - this came across to her as too little too late and only reinforced her feelings. Before you are tempted to so anything like that again, please post here. We are here to help you through this. As soon as you stop doing things like this you will feel so much stronger and better about yourself - only a good thing right?!
My rule before doing anything impulse is to sleep on it, it gives you a much better perspective and there is no rush, time is on your side.