<human>: Give me a shortened version of the text

This is about the third time this has happened to me this year, all with 26 year olds. I start dating someone exclusively, without the label of boyfriend or girlfriend yet. Things seem to be going fairly smoothly for 1-3 months and then all of the sudden they abruptly end it.

The last one, I knew he had intimacy issues but I figured it was something that would come with time. He literally offered to cook me dinner Wednesday evening and then dumped me via text on Friday when I asked why he was being so short. He said he "can't see this going anywhere and it takes him a long time to feel that way about a person." 

The one before that would drop by my house "just to say hi" because he missed me so much when I was away for 4th of July weekend. Then got drunk and blurted out "I have girls who I would go above and beyond to be with and then there's just you who I don't feel that way about. They would all text me all the time, always initiate plans with me, etc. so I am thinking things are going smoothly and then *bombs away* and I get blind-sided and it does not feel good. 

Are there warning signs I am not picking up on? How can I avoid feeling like I just got bull-dozed in the future?
<bot>: I have dated 3 guys this year separately for 1-3 months thinking everything was smooth sailing due to their attentiveness towards me and then get blindsided with a rejection. What am I doing wrong?