Co parenting after breakup

So I was blindsided by a break up 4 months ago and it was really hard on me mentally because I was deeply in love with my ex. Long story short I tried for months to fix the relationship to no prevail (he kept telling me he wasn't ready to try again) so I have just decided to move on with my life thanks to the help of therapy and knowing that I deserve better than to be strung along by my ex with his mixed signals and mind games (he's flirted with me, he's tried getting me to sleep with him, he's made empty promises about us getting back together and has just hurt my feelings over and over).. I'm over all his bs and so the last few days I don't text him unless he asks me how our son is doing (our son is 4 weeks old) and I don't respond to any text or picture (he sends me a picture of himself every morning for some reason 🤷‍♀️) unless it's about our son. I've told him before I couldn't be his friend because I still had feelings for him right now and it just won't work for me and he still assumed I was going to be his friend even after all the bs he's put me through. He seems upset by the fact I don't want to be his friend but honestly I don't care and I don't even feel bad about it at this point. My days are actually much better when I'm not talking to him because I don't feel stressed. My question is am I being unreasonable? This was our conversation earlier. Also I told him a few days ago that I wasn't going to talk to him unless it was about our son but yet yesterday he went from asking me about how our son was to asking me about myself and what I was doing. He doesn't understand why I'm doing this and honestly I don't think he cares since he's not getting the attention from me that he was getting and now he has nothing to feed off of for his own selfish needs.

Sorry the picture is blurry it's Snapchat and I didn't want to screenshot it since snap tells the other person you've screenshot the conversation so I took a photo with my old phone.