My Husband(31M) is suffering from guilt of a mistake he did 3 years ago. I am (30F). How do I clear his guilt?

(Backstory) I (30F) was born in Hong Kong and moved to Australia when I was 14. When I was 16 I started to date a guy from my school. Not to blow my own trumpet but that guy was very handsome and every girl wanted to date that guy since he is not only handsome but also well mannered and I liked him because he was from Hong Kong too so I could find someone to whom I could share all my thoughts in Cantonese. We dated for about 5 years and I can very confidently say that those were the best years of my life. He respected my boundaries did whatever I said and would always make time for me even in his busiest days. He even left colleges like University of Sydney, University of Melbourne which are the top universities in Australia to study with me in University of Queensland. Just when I thought everything was going wonderful in my life when I was 20 I met a girl who was envious that (an average looking woman) dating a very handsome man so she made up many lies and tried to break our relationship so that she could date him. This woman slowly broke the trust I had on my boyfriend and made me fight with him multiple times but even though it was my mistake every time it was my boyfriend who apologised every time. One day this girl made me test his loyalty and I being a naive girl agreed and agreed to book 3 tickets to a movie but that day I "felt sick" at least that is what I said to my boyfriend and they both went to the movie and she took him to the pub, got him drunk and tried to take him to her dorm. Which my boyfriend refused and he went to his dorm alone. I being happy that my boyfriend didn't cheat said that this was all a test my boyfriend finally had enough and he broke up with me and I don't blame him for doing that.

He after sometime fell in love with another woman whom he married I thought that I will get over him but all the time I was simply disgusted by myself for losing a gem of a boyfriend and even though I tried to meet some guys on bumble all of them were perverts who were just looking to have sex. I thought that this is all I deserve until 4 year ago when I heard the news that his wife had died and he attempted suicide. This made me feel even more disgusted about myself seeing that man would even give his life for his loved one he was hospitalized for about 3 months and I thought that this was my only chance to get my normal life back so I contacted his parents and instilled fear in them saying things like your son will not be alive if he will not marry someone else I was luckily a decently successful woman by that time so his parents accepted my offer and forced him to marry me against his will (Arranged marriages are pretty common in Asian families). After marrying I knew that he would be mad at me and he was he didn't talk to me and his parents for 6 months and slowly started talking to me probably because I was loving and taking care of his son whom he had from his ex-wife like my own son. But even though he started talking to me it was never like the time we were dating I accepted my fate and was thankful that at least I could marry that wonderful man.

Our marriage was all going normal and a month ago we went back to Hong Kong for my sister's wedding. Yesterday was her wedding and he got drunk with the others and when he came back to me he said that he's sorry for sleeping with a prostitute just after 2 months of her marriage because he absolutely hated me and he kneeled in front of me to forgive him and said that after he started talking to me he didn't cheat on me. I was genuinely shocked and then understood that this is probably the reason I feel like our marriage days are not like our dating days. I then thought if I against his will married him is it really cheating if he slept with another woman. I made him stand up hugged him and forgave him. Then when I went to congratulate my sister he made a confession post on reddit and is still feeling guilty. I never use reddit and this is my first post but my husband regularly uses reddit. I knew he made a confession post because I his laptop was open while he was using the bathroom and I happened to see that post. After he took his bath I acted like I didn't see his reddit post and I slept with him. This is the first time after our marriage that reminded of our dating days. When he fell asleep I could listen him again begging for forgiveness in his dream now I am genuinely worried about him and I don't know who to ask so please give me any advices.

I apologise if this post is too long or it violated any rules but I genuinely need help from you and now my husband is asleep since he is very active on reddit he will see this post so I think I have about 8 hours to get an answer after which I will delete this post so that my husband wouldn't find out. I am very tensed right now and I feel like I am about to get my boyfriend back so please help me.

TL:DR; I against his will married my ex-boy-friend who broke up because of me and after our marriage he slept with a prostitute he is now very guilty even after I forgave him how do I clear his guilt?