I 21M confessed to a 21F

I am 21M and I know this girl (21F) from 3rd semester of my college.
It was the 5th semester (2021) when we had our first formal interaction in the college library where she reached out to me to ask what things to study and from where. It was our last exam of that semester and she pinged me to solve an assignment together, we did it and we didn't even talked over the phone but just whatsapp texts and a few voice texts here and there. Don't know what happened was it just the hormones of a 19yo guy or what but even after knowing she had a bf I made my mind that she is the girl and I'll approach her once I grab a decent placement. I worked my ass off for the next 1 year and grabbed a job as a SWE at a fintech firm.

During our 6th and 7th semester she reached out to me several times but only when she needed something like assignments or only during exams. We studied almost all subjects together during exams but those too virtually on calls. You know we continuously talked for almost a week or two during exams and then the day our exams were over she never pinged me until the next set of exams arrived.

In the 7th semester, she was already placed but her bf wasn't and she knew I was good at problem solving, so she even started to reach out to me for getting answers to the coding questions asked by companies. I very well knew for whom she was asking but always helped whenever she asked for.

So, in short our 99% interaction were all on the phone calls and we had hardly talked anything else apart from academics.

Our college was ending in the next few days, so during my last exam I gathered some courage and asked her for a lunch to which she agreed on. We went on a lunch talked for some 2 hours and this was the last time we met.

Over the next few months, we moved to different cities started our internships. She pinged me very rarely (like twice a month) and that too just to ask if I have worked on the tech stack. I helped her with code and debugging stuff whenever she pinged. Then in March she altogether disappeared and pinged me a month later in April mid.

This time she started to text me on a daily basis, we had long calls like 3-4 hours too on certain days but again all just for programming things. Talking to her like daily made my feelings for her even stronger and I decided to confess her. I am highly introvert and shy, so texted her what I feel. Now she said I am her good friend and she hasn't thought about this and not in a state of these things rn in life and told that her bf passed away in March. I was shocked hearing this and had instant regrets for my confession.

But I also got my answer, I respect her decision and understand that she is already going through a lot and also maybe I am too much of a nerd for her. The issue is that I can't even leave her in such a bad phase of her life because she needs me for very small things and staying fucks up my brain because I am not okay with she just pinging me when she needs some help from me. She still calls me for help as if nothing had happened.

I just keep thinking of her all the time and just wish if every notification is her message. I am really into her and I just don't want to hurt her by saying nasty things. Any ways to deal with this. Thanks