Don't know what to think...

So I blocked a girl who is known to be a "hoe" off of my husbands snapchat months ago ... she is now back on his Snapchat ... when I asked him why she was back on it and what they were talking about he got defensive and says I'm crazy... I was calm about it and he just blew up.... I know it's a stupid question but and I just being paranoid or could he be cheating on me ? He's been acting different and doesn't ask me to have sex with him anymore or ever want to....