We are together for 5 years and I love her so much

What did you do that was so bad? How long have you guys broke up with. Who broke up with who?

Well there not going to be overly happy with you because you've just left them, but it was for right reasons I'm sure, just give them bit of time and space and gradually tell them your sorry and you still want to be mates,xx

You don't, you accept the break up, start healing, and move on. Saying sorry will not bring her back, and it will definitely not make you feel better. Move on, go no contact.