Advice!!

I met this guy on a random video chat. Had a really fun, started talking daily. He was very stressed about his placements, sat through with him when he applied for the firms. Daily used to hear him out whenever he called me to be sad or rant. He got placed, felt very happy and slowly he stopped calling or texting telling me that he saw me as a friend and he treated his friends like this only (not talking to them.

Now I also am very against the idea of begging for his attention. I left him and the calls and texts stoped altogether. I somehow got over him and he called me again telling me he is high or something, and "mjhe abhi yaad aya ki you also are there to talk". I yelled and told him that I can't talk and ended the call. He started reaching out daily again and I was like maybe this time he is fine Mwybe. After a few days he started asking me for advices on CAT (I am a BLACKI IIM graduate) and other stuff. At the back of my mind I have that he might be using me and have started to ignore him. Am i being stubborn or something or is it right on my end to do so. He hasn't even realized that I have been ignoring him itne dino se.