<human>: Can you give me the gist of the text in a nutshell?

I thought our relationship was going really well, we've been happily together for four years and talked about the future, if anything he was more invested in the relationship than I was. 

Suddenly a month ago he changes, starts saying he doesn't love me but refuses to dump me. (Around this time he lost two family members, it didn't seem to affect him apart from his feelings towards me). After him telling me he doesn't love me three times within two weeks I eventually tell him we need to fix things or break up. He tells me it's over and ignores my calls/messages and deletes all accounts we shared.

He also left our friend's group chat and has stopped talking to all our mutual friends, saying they're mine and I can effectively have them. 

It's been a week and I've been practicing no contact but the occasional post from a mutual friend leaks through. He has started favouriting this one girls tweets obsessively and liking all her photos on instagram, which is very unlike him. He has also been out drinking, which is also unusual as he doesn't usually drink. It's like he's had a sudden personality transplant.

I have no idea what to do, I have no closure and it's really difficult to move on when I still have a lot of his personal belongings (including Xbox and games)
<bot>: Boyfriend suddenly changes, leaves me and abandons friends. Still have all his stuff and finding it hard to move on