Nothing i can do about it

Last year, in my office i became friend of a girl. Being married guy, my intention was not at all to look beyond friendship. But i didn't have controlled over the love and it happened between us. She thought i was not married. So when we felt we have feeling for each other, i just confess that i am married but the love and feelings for you is real and natural. I confess because , i care about her and couldn't keep her in dark and be the reason of her tears. After confessing, we carried this relationship as friend kind of. But we just can not run away from the love feeling that was developed. She was the type of girl( her nature, behaviour, care), i desire in my whole life. So i couldn't controlled of love being developed for her. I regret this step in future. But it was what it was so we use to meet , love and care about each other and this continued for more than an year. But around 3 4 months ago, we mutually decided that this is wrong and it's better not to continue. She use to cry a lot of being in that situation that she loves a married person.i use to cry seeing her tears . I was couldn't walk away from that love. So we decided to stop all the connection between us. I just don't want to be the reason of spoiling her life and making her cry. So i followed to be away from each other. It's like, we know we love each other,our happiness is in eachother and nothing we can do about it. I told in the starting phase of parting our path, i just need you beside me and i can handle everyone. I told her, just say me that you are with means i will confess my love to whole family and through legal ways we can be together. Just need you beside me. But she said no as she don't want to the source of unhappiness for many person by opting for this . It was not her mistake at all. It was mine as i was married and developed love for her.i think we don't have any control over this love. We are not talking to each other. We miss each other.but we can not be together. She is getting married. She still loves me and so do i but because to make all others happy we can not be together. Nothing i or she can do about it . I feel so low and depress till now. It being 4 months of parting ways and there is not a minute i haven't think about her from inside. I don't know what to do. Just broken and living a meaningless life.