Same thing happend to my sister + she was at a similar point as you with her usage at that time. She lied to my parents about what the hospital visit was for and they never found out. So your parents have no real way of finding out what those charges are for, so that decision + where you go from here is on you. I will share my / mysistes story below tho:
My sister made the same vow that you did after she OD'd, it scared the shit out of her as I'm sure it did to you. She was able to stay clean for 3 months but eventually she started using again because like you she was using with friends, and when your around ppl using its hard to not eventually get drawn back in. My parents N I didnt find out about any of this untill 2 years later when my sisters H addiction got so bad that she was using about a G/day and almost died in a head on collision while diriving nodding off. I went to her apt when she was in the hospital to grab some stuff for her for when she came home and found a spoon. We knew something was up with her before the accident, I didnt think it was drugs thought she might have just been depressed or something or just changed thru the years.
The next year after finding out everyhting and getting her to finally come claen with us about her use and everything was absolute hell. We all did our best to support her - she was detrmiend to beat her addiction on her own and not go to rehab. She was in and out of detox, living home w/ my parents and even then she was still somehow managing to score and use. It killed my parents - they called me crying all the time, I felt terrible we all jsut felt so hopeless. I was in medical school working like 100 hours a week felt like i was being a bad brother by not having any free time to try and help her. I couldnt sleep at night so I lurked these forms, read the news about the heroin epidemic and basically just prayed every day that I wouldnt get the call that my sister was dead from an OD.
Nothing was getting better for any of us. I was home one weekend basically babysitting [we would drive my sister to and from work to try and stop her but addicts have thier ways around however you try and stop them] and broke a deal with her that I would take her to score one last bag and then i was taking her immediately to the hospital and she was gettign the fuck out of this state and giving rehab a serious effort, minimum 30 days.
Took her to the ghetto, she scored, did it in seedy fuckign bathroom, she was nodding, never been so sick to my stomach watching all of this seeing my sister basically drooling on herself in my passenger seat, crying my eyes out, took her to the hospital, stayed in there with her all night. They had no beds at any of the detox places near us, it was so frustrating, took her home bought a ticket and set her up with a place in florida. She really really reallly didnt want to go esp when sobered up next day. Was doign good intially, had several relaspes, but now im so proud to say that she got her 6 months a few weeks ago.
One piece of advice to you / reason i shared this with you / reason i decided to make my first post ever was becasue I feel that you are right now in that same excact place my sister was in when she OD'd. if that day she first OD'd had come to me or my parents and told us and not hid the real reason she had to go to the hospital so much of our pain could have been avoided. It was over 3 more years of torment to all of us that could have possibly been avoided. Don't be ashamed of your use, believe me your parents will be so much more accepting + supportive than you expect, They will help you and they will NOT be ashamed of you. They love you, and once they understand more about addiction and drug use I can promise they will never hold it against you. It will bring you guys closer and you can stop yourself from going down this long, shitty fucking road. Hope you reach out to them I guarantee it will be the best decision of your life.
pm me if you want any support or to talk or have any quesions