It makes me angry that my wife responds to her WhatsApp messages while we eat. I have told it to her but she won't stop. What can I do the issue affects me less?

Try sitting your wife down and having a serious conversation With her About how it makes you feel. Tell her exactly how her being on her WhatsApp during your meals affects you and the reason you want her to stop, for example, maybe tell her that eating together is a time where you two can communicate and talk to each other, and that she can answer her WhatsApp afterward as much as she would like. Communication is the best way to show your wife that you respect and listen to her and would like the same treatment as well.

A therapist once told me that anger is a secondary emotion; this means that your anger is actually a reaction you're having to another feeling. How do you think your wife's inattention at dinner makes you feel, underneath the anger? Do you feel lonely, like you wish she would talk to you more? Do you feel anxious that she's not interested in you? Try to dig a bit deeper into how your wife's behavior makes you feel. Once you can put your finger on that, you'll have a better understanding of your own reaction, so it may be easier to control. Bonus: you may be able to communicate more effectively with your wife about it.

It's good you are able to name your emotion as anger, and it may be helpful to explain it to your wife in a way that allows her to understand why it makes you angry. Another important aspect to note is discovering why this action of your wife is making you angry, and why your wife continues the action. It could be something as simple as conflicting expectations of the situation. For example, if your wife uses eating time as her downtime to relax and catch up to messages she missed on WhatsApp, while being able to talk to you -- that may make her feel more comfortable while it may make you feel ignored, neglected and angry. Sit down and try to talk about both sides, there may be another time she can use her Whatsapp or another time you can get that needed attention from her.