TIFU By trying to look for forgiveness and fix the past.

Some backstory so you can understand. I dated a girl (let’s call her “J”)a long time ago , me and J were a long distance relationship, long story short it didn’t last , after we broke up , I treated her very badly and I’m ashamed of things I made her do. It’s always in the back in my mind what I’ve done to her even to this day I was horrible person. Fast forward to presents day , I’m currently with the girl of my dreams(let’s call her “Z” ) me and Z have been dating for 5 years , we even have a kid , a baby girl. Words can’t describe how much this little girl means to me. Having a girl , made me realize what I did to J was truthfully awful and not okay what’s so ever, I kept thinking what If someone did the things I did to J, to my little girl. It made me feel guilty beyond I can describe. Ever since , I’ve been trying to say sorry and seek forgiveness to J but she kept blocking me whenever I tried to talk about it, and I completely understand why she. But in the back of mind was always that guilt , fast forward some more , couple of days ago , I was on some nsfw subs because reasons , I came across this post that mentioned J’s username, If anyone I had her nudes , this made me feel some way , I’ll say this right now(it’ll be important later ) I still have feelings for J but as someone who just cares about her well-being and not in the romantic way whatsoever, I have my life and she has her life now I don’t want to ruin what I have anyways I just wanted to tell her what I saw because if that was me I would like it if someone told me , and if possibly apologize for my actions. First time she hasn’t blocked me , I told j what I saw and she told me she knew about it and thanking me for letting her know, then I asked if we can talk , she asked about what , I told her I want to apologize for what I’ve done to her and how her life was going, , she told me fine and she’s been dating some guy for couple years or something, I was generally happy for her , she asked why I wanted to say sorry because that was 6 years ago since we broke up and I did those things to her , I told her it’s always in the back my mind , and guilt was terrible, I told her I cared for her but like this “I still have feelings for you “ , but I didn’t say what kind of feelings , that’s my fault honestly but I thought it was pretty clear , what I feelings , I meant friend feelings, I honestly and 100% don’t want to do anything with her , I just wanted us to be okay , I was seeking forgiveness so I just move on and not have that guilt back in mind anymore. Fast forward that night I told her , I fell asleep and Z worked late that day, she came home , and she went through my phone, she knows my passwords because I have nothing to hide , she’s beyond more then enough for me , she’s my best friend, I only want her and nobody else , she’s honestly the best girlfriend and the best mother she can be to our little girl. I’m grateful she stuck with me so far. She saw my messages with J , like i said I only sent her “ I still have feelings for her “ but not those feelings, and she saw that , and she thought I was trying to cheat with her with J but that’s from the truth I wanted to be just be okay with her , this guilt has been killing me for the so long. Now we’re in the biggest fight in our relationship. Idk what to do , I don’t want to lose my best friend. I feel so awful. I’m being honest when I say I just wanted me and J to be okay that’s it , be bygones be bygones. I didn’t want presue anything with her she has her life and I have my life , I didn’t mention Z or my little girl , to J I didn’t have enough time to tell her (she had to stop texting me at 10 for some shit idk) and I was gonna build up to it. I really don’t want to lose my best friend. I don’t wanna lose my family. I just wanted this guilt gone. If anyone has any advice that would be helpful. Please and thank u. Tl;dr: I told my ex that had feelings for her but didn’t mean those feelings and now my girlfriend and mines relationship is on thin ice.