Hi everyone. Sorry for the bad english

I am a 24 year old boy.

A few months ago I started to develop a very strong relationship with a 22 year old friend of mine(F).

I have already known her for 2 years as she is part of the company I frequent but for 5 months now she has started writing to me, we talk every day from morning to late evening(2:00/3:00 am), we do things together, we talk a lot and we even go out alone, only I and her. without the company that we frequent-

The problem comes from the fact that she is engaged with a boy from the company (3 years of relationship) and the problem has arisen several times that she says she feels she is doing her boyfriend a disservice by behaving like this with me. Because if her boyfriend did this to another girl she would go crazy.

I bought a house and from the moment she found out she started saying that she wanted to help me with the furniture, with the design of the house, that she would come to visit me several times, to watch movies, play games and spend time with me. Just me and her.(the house will be avaiable at July)

She has always sent me ambiguous signals, ambiguous phrases, ambiguous ways of acting. She made a jealous scene at me because she thought I liked another girl

In any case we continued with this relationship. 1 month ago she went on holiday for a week with her boyfriend and although she said she wanted to detach herself from our relationship(being that we write or call each other every day from morning to night), she didn't and in fact she continued to write to me while she was with her boyfriend on the other side of the world.

when she came back, we saw each other and in the evening everything was fine. When she returned home she wrote to me telling me that she felt guilty towards her boyfriend, because she hadn't told him that she and I saw each other that evening. I tried to understand if she was interested in me because she always says that she knows the best solution would be to reduce the frequency with which we talk but she can't do it (she doesn't know why she can't).

Consequently I thought that maybe she might like me, I tried to get him to bring up the subject but nothing. She said she knew very well what she should do (move away and gain some distance) but that she couldn't do it.

We went to sleep as it was late and the next day she wrote to me telling me that there were some things I wasn't telling her, after which she asked me if I likes her. I replied that I have an interest in her, bad response. He started saying that it wasn't okay, that it was better to stop talking to each other. So I took courage and asked her if she likes me.

And she responded with a curt "No, I thought you understood."

After that I managed to make her understand that mine is just an interest and that I don't like her that much. (It's not too true, cause i like her)

So for now I have saved this friendship relationship that we have, but I realize that the thought of this hurts me, I don't understand if it's true that she doesn't like me or if she doesn't even know exactly. If she is afraid of leaving her boyfriend or no.

I don't think you would write to someone on the other side of the world every day, while you're on holiday with your boyfriend if there wasn't some kind of interest, but from what she says, she doesn't like me and in fact she told me that if If I had told her that I like her, she would have ended the relationship we have, because it wouldn't be fair to her, her bf and also to me.

Now I find myself not knowing what to do. I don't think I could go back to how we were at the beginning, going out in the company with the others, her and her boyfriend. Pretending nothing happened. But at the same time I understand that this situation is difficult for her because she can't tell her boyfriend and this ruin our relationship, because she puts her doubts on me.

TL;DR Do you have any advice? she really doesn't like me? Because the signals it sends are very ambiguous and strange. even my friends all thought she liked me.

And now I find myself at a crossroads where the easiest but most painful thing seems to be to break off this unhealthy relationship.