Is married Coworker being nice or flirting?

Married 38M coworker likes me 33F? First off, let me say that I have no intentions on talking to a married man, or dating a coworker. I have a boyfriend too. However, I'm not sure if my new trainer/coworker is just being nice to me or if he is trying to flirt with me. I recently began a job about 1 month ago. My married trainer/coworker introduced himself then immediately forced Starbucks coffee upon me on day 1. This was after I said, I'll just drink the coffee at the office but he was very insistent I guess to welcome me? (In my head it's because I am not trying to accept gifts from men) he's goes out his way to talk to me every single day all day about things that's not even work related such as his property he’s purchased and cars he’s paid off.. Within the same month of me getting hired, my birthday had passed. I guess he felt bad that he forgot and was really insistent on ordering/buying me lunch although I turned it down he got me food anyways. Something tells me he didn't do this for the other people that he's trained. He also forced me to try on his hoodie in case I get cold even after I told him that I will get my own jacket but he helped me put his jacket on anyway. so I'm just not sure if that's just him being nice. I understand he's supposed to be training me, but he goes out his way all the time to talk to me about random conversations with lingering eye contact, he often stands really close while talking to me, anytime he sees me talking to another coworker he pulls me to the side and talks crap about them but smiles in they face lol. It's like he's trying to isolate me for whatever reason he hasn't text me anything inappropriate, but he did state twice that “customers wants to talk to pretty girls like me?

Is married Coworker being nice or flirting?
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