Please help me with your advises,

My boyfriend and I have been dating for 1.5 years now and we moved in together earlier this year because we decided to get married end of this year. The wedding dates were fixed and everything is ready for the ceremony at the end of the year. But I have noticed a lot of changes in him after we moved in. He is not the same caring person that he used to be. He doesn’t really text me or calls me as much. Whenever we have an issue and when I speak up he admits all that as his fault and shortcomings and keeps quiet. And he keeps saying sorry for all the mistakes.

I was really broken by what happened a few days ago. Some of my friends wanted to treat me and my BF and they arranged a date with us like one month ago. I told my bf about this and he promised me that he will come. He was looking forward to meeting them and their husbands too. Somehow, close to the date, he said he has a family outing during the day but he will surely come as it was a dinner arranged by my friends. I called him up so many times before I left home and on my way..at last, his mom picked up the phone and passed it to him and he was drunk. I was so ashamed and didn’t know what to tell my friends and he took a cab and appeared very late for the dinner. That was ridiculously embarrassing.

And after 2 days it was my Dad’s birthday. I told him so many times I was going to make a cake and stuff but he forgot on the day and didn’t even ask me what I did or how it went. He didn’t even wish my dad although he met him on that day.

I am so disappointed with his behaviour. Is he being selfish? I don’t know if I should move out and call off the wedding. but if we do my parents would be really very upset as they are having high hopes for our wedding. I haven’t told my family about any of these issues. I don’t know how to get out of this unhappy life. My BF doesn’t want to talk about anything. He acts all normal every time and asks me not to think about these issues. What should I do? Please help me.

Thanks you so much