If a restraining order is in place, please do yourself a favor and respect it and have no contact. Generally most immediate orders (if granted) are for only a month or two, depending on the situation. If there is no order in place, it is actually quite difficult to obtain one, but since we don't know the circumstances of the situation its hard to say if this would even be approved.
If someone is upset over your actions and you are regretting your decisions from that day, try to center yourself first. Find the cause of your reaction and try to prevent it from happening in the future. IF you were angry over something and made verbal threats, start there. You should focus on yourself and learn what works for you to make yourself a better person.
If this person does not want to communicate (as I would suggest trying to reconcile and admit your wrong doing or apologize but if they won't speak to you that will be difficult.) the most you can do is wish for yourself and them inner peace and forgiveness. Time may not heal all wounds but distance from an even can soften it, so its not to say that in the future they may be willing to communicate and accept your forgiveness.
I am sorry if this is not more helpful. I wish you the best in finding your answers.