Ex boyfriend playing hot and cold

So for the past 3 months my ex boyfriend has been playing hot and cold. One moment he is calling me by my pet name, pretending to tuck me into bed/make me hot chocolates/run me baths over text, The next minute he's telling me to leave him alone before I lose him when he often started the conversation.

Today I've deleted snapchat because he was seriously stalking me on there, I went to my friends graduation yesterday and posted several pictures on my snap story, after a while what I noticed was within 1 minute (literally) of me posting them, he was viewing them.

I messaged him and he started off being nice again, but said he was lonely, boring and had no friends. I offered to meet with him and the next minute he is telling me to leave him alone before I lose him.

We have met up once since we broke up, it is around 2 months ago now and when we met up to exchange our belongings (it took me 3 weeks to get him to give me my things back) I said I was going into town to do some shopping, suddenly he said that he'll join me. He spent 3 hours with me where we got a milkshake and played some giant arcade games. When we had to go (because of parking tickets)he gave me a really tight hug and I haven't seen him since. I know that we both belong to a church group, which he has not been to since we split up. I know he's actively avoiding places I might be.

I don't know what to make of it, on Sunday we were having a lovely conversation which lasted quite a while (half a day) and then he suddenly says that he needs time to think.

I've messaged him today and have got no replies, which is the first time he has totally not replied to me. But yesterday he was viewing my snap chat story every minute.

He has always viewed my snapchat story within the minute since we broke up, when we were together he never used to view it. But since we broke up he is viewing it every minute. The only difference is for the first month he used to message me after he'd view my snapchat story. But for the past month and half he hasn't messaged me as much, only once or twice.

I've reached the conclusion that I should just leave him to his own devices now, but I dont know if deleting snapchat was the right decision or what this all really means.

He started off saying that we should keep our snapchat streak going, I didnt want to, so didnt. Now he's saying he needs time, but is always viewing my story.

Just to put this situation into perspective he's 25 and I'm 21.