Do I wait for him to contact me first?

Hi there. There has been a no contact period of just over a month now. We were together for 7 months and were deeply in love. He told me over and over that he ha never felt such love before and was even speaking of marriage. We had a great deal of loyalty and passion for one another so that wasn’t the issue. Our problems which were never fully understood were about culture and class differences. I have university post grad education, he never went to university, and I earn much more than he does. Our culture/ religion is also very different. He broke up with me during an argument over whatsapp (terrible style) which was probably due to cultural misunderstanding. It was my 50th birthday and he dropped dinner plans with me that morning, not seeing it as that important. So, I believe our relationship, which has some work needed, can be saved. I have no idea how he feels but he must be determined to stay apart as he hasn’t contacted me at all. How does the contact resume again so I can get to resolving our issues and getting us back to bliss? Do I wait indefinitely? Or do I write the magic letter? Thank you for reading this!
Ps. I’m an emotional mess and miss him terribly

Write the letter. Let him know what you are doing now. Make sure he reads it. Now do you have to wait? Nope initiate. Try texting him messages that doesnt require him to reply. Something you saw or something you remember. Example “hey i passed by our favorite restaurant and it reminded me of the time you dropped the meatball. Anyway i just wanted to let you know you were on my mind. Take care.” A simple text would be good enough. Keep me posted and I’ll teach you more of those text