Hi OP. I had to reply to this one. He sounds exactly the same as my x husband. He started out nice, although looking back I definitely overlooked red flags.
When I met him 16 years ago Mumsnet didn't exist unfortunately. Luckily for you, you have this forum to give you the insight and perspective that I missed. I am also a trustworthy, loyal etc person which is why it was easy for someone like him to take advantage of me. I would never expect someone to pretend to love me so that they could use me, because it would never occur to me to do that! But unfortunately I have learned the hard way that people do.
Over the years my husbands treatment of me went from nice in the beginning and very gradually got nastier and nastier. Never violent, but subtle put downs, not coming home, not listening to me, saying I'm boring, only being interested in himself. Lies lies lies about everything! Stonewalling, gaslighting, then I found a second phone and discovered an affair and loads of other girls blah blah blah. Then a serious drug problem came to light! And his drinking was a nightmare. Life became more and more awful and of course I felt to ashamed to talk to anyone in real life which didn't help. I discovered he was into choking women and a load of other sexual stuff which he kept separate from me. To him women are objects to fuck and use.
Anyway, turns out I didn't know this man at all. We are married with 4 children!! He was using me to make him look like he was a good normal family man. When in fact I have now discovered that he is a very damaged man who was raped by his uncles friends at about 6 years old and grew up with a father who beat up his mum and was an alcoholic abuser.
He is a pathological liar and cheat. He needs new women/sex and drugs to make him feel ok. He has zero empathy and is a totally self centred user. I have learned that he is a covert narcissist and I would say your partner definitely is one as well. Please read up on it. You will be shocked how it rings true.
You are vulnerable and he is taking advantage of you. You need to educate yourself about the covert narsissist and how to end a relationship with one in the best way. Otherwise they can make your life hell. Mine did. But thank god me and the kids are not with him anymore and I am able to start improving my mental health so this doesn't happen again. The longer you spend with this nasty man the more damage he will do to your mental health and life. You are not being insecure, you are being abused again and you need to get out.
You can trust again in time. Because when you read up about the covert narsissist you will learn the signs that you can spot very early on to prevent yourself from falling prey to one of these horrible men again. And one day you will meet someone who is a good person just like you clearly are. Take care of yourself x