How can I control the tears?

I have always been a sensitive person. I am very empathetic and feel way too deeply, however I feel that my emotions, and lack of ability to control them are affecting me negatively now.

I struggle to have professional conversations at work, because as soon as I feel flustered, I start crying. I can't talk about hard days, or challenges that I faced, because, you guessed it, tears. I can't have any real conversations where anything serious, sensitive or emotional is discussed, because the waterworks always turn themselves on. I have hit a point where I get so anxious about this, that I have panic attacks about meetings or phone conversations. I will email or text every time if given the option. I get so embarrassed and to be honest, I am avoiding a lot of social interactions, because I am just so scared of always being the emotional, crying friend.

Being empathetic makes me good at my job and it is who I am. I am a good listener and am always there for people - but how can I control the tears? I could be an even better support to the people around me if i could communicate openly, without the tears.

Please offer me some help.