I'm having trust issues

Ok. When I first started dating my husband when I was 17 and he was 18.5 I went on a trip with my friend and found out he was having phone sex with a girl. I considered that cheating. 
Since then I've had trust issues and nag him a lot if he starts talking to another girl. But now that we're married he said he would never do it again because he knows what will happen. 
His old job which was less than a year ago he worked with a girl named Jessica and he always talked to her and had her number and had her as a friend on Facebook. I felt ok with it because she's married too. His new job now, he is working with a girl named Jessika lol. He talks to her a lot because they have the same interests but she's not married or anything. He just got her number 2 days ago and said he was going to tell me but didn't until I said as long as you don't have her number I'll be fine. 
He had her as a friend on Facebook too but somehow lost both of them on there. He looks them up a lot and I asked why and he said I'm just seeing why they're not on my friends list. 
They're both beautiful and the current Jessika lifts weights and is fit and I'm very insecure and worried he might want her instead of me but he keeps telling me she's just a friend. Would you trust your man with other women's numbers?? My mind just can't let go of the past and it's ruining me 😢
This girl is coming over to our house today which is going to be weird. We know where she lives and now she's going to know where we live. Not very smart but he basically said it was ok that she comes over without discussing it with me first. Ugh 😑. She's coming over to show me a pistol, I said she's coming over to kill me so she can have you lol. 
Sorry I just need to vent. I have no one to talk to anymore. Lost my closest relatives.