<human>: Hi r/relationships!

My SO has been extremely secretive about his phone lately (more than usual), and it's making me feel a little crazy and very insecure. When we're sitting on the couch together he turns his phone to a really awkward angle, in what seems to be an attempt to keep me from seeing what's on the screen, even when I'm very clearly not looking. If I ask who he's texting, he says it's none of my business and he deserves privacy. This obviously makes me more suspicious, because I feel like if he must be talking to someone who would upset me if I knew who it was or having an inappropriate conversation (like the old adage "those who have nothing to hide, hide nothing"). Every time I ask he gets more defensive and I feel more insecure each time he refuses to answer - it's a really frustrating cycle. It always ends up with both of us feeling upset - me because he won't just be honest with me and tell me what's going on, and him because he feels his phone is private and he shouldn't have to tell me what he's talking about or who he's talking to. His phone is also always locked, and I noticed he's been putting it on airplane mode more than usual when we're together. 

My question is - is this kind of secrecy normal for guys? Am I expecting too much when I ask who he's talking to or what they're talking about? How much privacy do you give your SO when it comes to their phone?

Can you give me a shortened version of the text?
<bot>: My SO is extremely secretive about his phone and it makes me feel insecure. What do you consider "normal" phone privacy in a relationship?