<human>: Give me the gist of the text in a nutshell

I'm trying this post again,  shortening it to just the problem at hand without all the background since I kept getting advice about everything other than what I asked about.   

My boyfriend is strangely close with his ex wife. They are friends and have a lot of friends in common, so they hang out often. They text each other about stupid every day things, sometimes when I'm with him. He will go to her place to fix things around the house for her.  They have keys to each other's houses (to pet-sit for one another,  they share dogs).  He doesn't make a big deal about it so I try not to as well, but it's weird to me that they are so close. I can't help but worry that he and I will never be as close as he and his ex are. My question is, am I being silly and need to deal with my insecurities on my own, or is his relationship with her inappropriate and something I should rightfully be bothered by?
<bot>: My boyfriend is besties with his ex wife. Should this be a problem for me, or am I being silly?