I made a friend but now he's ignoring me. Should I also ignore him?

Anonymous
I am and introvert but there's this new guy that insisted on becoming my friend. (Well, he asked me to follow him on social media platforms, which I did.) He's a little flashy and an extrovert from the way he talks but he was a nice guy who would listen to me.

At first, we would text about anything for hours. We shared similar tastes in music and hobbies and that made me comfortable with him. He would even share some music to listen to or something to read.

He shared some of his personal life, about his exes and family. He also talked about how he doesn't want to be in a relationship for now and he would also warn me to not trust guys easily. I also became attached to him since I only had a few guy friends, he's like a gentle brother that I don't have. He's gentle and sweet toward me, he knows that harsh words or comments will make me anxious and would refrain from talking harshly and would change his tone to a low one. There is also one time when I told him that I'm cold and didn't even hesitate to let me borrow his jacket.

He would ask me about things that I think he knows the answer already. He also asked me if I would like to hang out with him alone but after that, he started to visit me and ask if I would like to have lunch with him and his friends. If I don't go with him, he would say that his friend will miss me.
But then, one time he asked me if I know a girl (my acquaintance) and I told him yes. I think he likes her and told him I would help him to be with her. After that, our time spent together gradually decrease.

I think, he's with the girl now. Should I withdraw with the group I made friends now to let him be? Because he's ignoring me now. Should I stop texting him even though he's a sunshine and a nice guy? Maybe he's ignoring me not to hurt his girlfriend? To be honest, I didn't know what I did. He just started ignoring my text and ignore my existence at all.
I made a friend but now he's ignoring me. Should I also ignore him?
5 Opinion