How to deal with a labmate using my method without credit? So, I have made a presentation on my thesis at my workplace (a lab where I am a postdoc at), people make presentations on their current work so it is meant to be a meeting where we know each other's work and can collaborate etc. 

So this person takes my method and idea (as in application relating dataset and on exactly what problem to solve) and he announces he will basically do the same for his work (on the same and a similar dataset) only a week after. I gave him hints that the work is identically the same and I could lend the code if he wants to and we could work together, he warded off all attempts, I have given hints to our advisor too but he is like Idk. 

Today he announces that he has good results (though he still needs to implement another part).

Meanwhile I did send my paper to a journal and it said I needed more testing (major revision) but since it is a different affiliation I can not do an extensive testing on my own using the new lab resources, besides my code is not well optimized, so I was thinking on using another framework to re-implement it. 

MY POINT is, shouldn't HE offer to work with me in this case? Shouldn't our advisor meddle and put us to work together? It is true that anyone, anywhere in the world could do the same thing and publish -but- we are in the same lab and he clearly just snitched off my idea. If I were in his place, I would definitely offer to work together. 

How can I deal with this, especially since I feel I will look like I am the "difficult" person. In my previous lab, people were really ethical about this, once you use someone's idea, especially if it is a whole paper kind of work, you include them in paper.
Speak to your advisor. You write that you've already done so but he's like "idk". Well, make sure he knows. Don't "give hints" and speak clearly. If you're assuming that by giving hints he will understand you, don't! This assumption is dangerous, and much more often the other party is not really sure what you mean. Here's an example of giving hints gone bad. The other members of the lab were giving hints to RH88 not to come, but RH88 did not get it, went anyway, and then after he's moved he finds out they were giving hints. 

If your advisor is clearly aware of the situation, knows what your grievance is, and is still "idk solve it yourself", then it might be time to re-evaluate your time in the lab.