should I text my ex?

My ex recently blocked me because I posted a guy on my Snapchat story. I don’t want him to think I’ve moved on and I don’t want him to hate me. I texted my ex on Instagram asking if he is mad at me or something and he left me on read. I’ve tried to get over him but everyone I talk to it’s not the same, I just really miss him. What is the perfect thing I can text him to let him know I still care about him but not too lengthy so I don’t look weird. Thanks! (Also I understand a lot of you are going to say I should just leave it alone but life is too short to not get your point across and to leave things alone, I’m going to tell him how I feel one last time and if it doesn’t work it doesn’t work but I’ll never know if I try because he obviously still has feelings for me if he blocked me even though he is hooking up with another girl right now)