Stopped dating, going on vacation together now?

Hellloooo :DAt first, my apologies for this way too long post, but i really need some advise haha.So, a while back i posted this : http://ift.tt/2iUuS7u, that date ended a month after that post. We had a lot (A LOT!) of arguing, we had fights on Whatsapp about it and it wasn't getting any better. The breakup was rough, because we both didn't want to lose "it" and eachother so it did hurt on both sides. After stopping with the date i remember i thought "This was it. I'm not going to see and/or talk to him anymore", but the opposite happened. He started sendings texts all the time, very happy messages and that he liked to talk to me. We met i few times, had dinner a few times and last Saturday he came over to my place. Just as "friends" i think.I need to tell you guys another important part about this story, because me and my ex-date work at the same company and we use an internal chat tool. We had been talking on that chat all week, and all the communication was like very "edgy". It was reeeeealllly funny because we were like bitching on each other, which was hilarious. We had great times laughing at the office. He also said some things that made me think that he wasn't just after friends. I told him i was seeing this other guy and he told me he didn't want to get "swapped" with that guy because he loves to talk and chill with me. At a sudden point he send a kiss-emoji to me on the chat, so i responded with "Ah, you are capable of giving kisses again?" "Yes, sure!", "Ok, come and give me one", and within a matter of minutes he was standing next to me (no colleagues were around) and he gave me a kiss on the cheek and hugged me.Now, this saturday he was at my place. It was really really very comforatable with him, we were chilling on my couch, playing some games and watching a movie. Then we made dinner together and although nothing happened, i felt some kind of tension between us. He hugged me when he arrived, when he left, and he gave me a massage because my back was hurting. When i asked him which tea he wanted he replied with "You" and he was constantly challenging me, by pulling up his t-shirt, coming really close and things like that.Now, he came up with this idea of going on winter holiday together this march. He has a house there, so he said "Ok, let's go there together by car and have a nice week of holiday". I love that idea, because i'm crazy about winter holidays and it's fun being together so i'd sounded like a great idea. At first i thought he was joking, but he now asked to get off from work in that week... so it is serious.I would love to go on winter holiday with him, but i don't know what he is up to.... i don't want to ask him because it could make it worse again. But i know, deep down inside, that i still really, really like him.......What to do? Any ideas about what he is doing? Could this be as just normal friends, or is there more to the story?