Nanette Bowen, from Llanelli, suffered a nervous breakdown and was unable to return to work after being harassed over a three year period, according to her solicitors.
Hywel Dda NHS Trust has now been told to dig deep for damages by her union, who helped Mrs Bowen bring the case to Swansea County Court.
The 55-year-old information manager had worked at Prince Philip Hospital for more than 28 years, working her way up the ranks, from porter to information manager, reporting directly to the chief executive.
In 2000, Eric Lewis became her boss, following a merger of Llanelli and Dinefwr trusts to become Carmarthenshire NHS Trust (now part of Hywel Dda NHS Trust).
According to statements issued by her union, Unison, and her solicitors, Thompsons, Mrs Bowen's life became hell over the next three years.
They claimed Mr Lewis was aggressive towards her, made sexual innuendos and banned her from attending meetings vital to her job.
She was signed off sick with stress and suffered panic attacks. At one point she was rushed to hospital with a suspected heart attack.
Mrs Bowen, who had been the main breadwinner in the family, said: "The NHS was my life. I had always felt great loyalty to the trust and worked to the best of my ability in everything I did. I feel bitterly let down by the trust, which did not do its best to support me when I needed it most.
"My life has been ruined by what I went through during those three years.
"At this stage, I cannot contemplate returning to any form of work and I am still receiving counselling to help me control my panic attacks. Without the support of my family and colleagues, I would not be here now."
Dave Galligan, Unison's head of health in Wales, said: "It is disgraceful that this bullying and harassment continued for so long and led to a severe breakdown. Despite her complaints, nothing was done to improve her situation. As a result Mrs Bowen has suffered terribly and the NHS has lost a skilled and dedicated worker.
"I am pleased that UNISON has helped Mrs Bowen win her fight for justice. "The compensation will go some way towards making up for the horrendous situation she was put in. "Despite her complaints, nothing was done to improve her situation. "As a result Mrs Bowen has suffered terribly and the NHS has lost a skilled and dedicated worker. "This case is a warning to employers that they need to listen to their employees' concerns and act sooner rather than later, or face the consequences." Amanda Jones, from Thompson's Solicitors, added: "Work related stress cases, particularly those involving bullying and harassment are very difficult to prove.
"This case is a warning to employers that they need to listen to their employees' concerns and act sooner rather than later, or face the consequences."
A ruling on the level of compensation is expected over the next few weeks.
Mr Galligan added: "It's going to be a substantial, probably a six figure settlement. It is deserved, because not only was this a particularly bad case, it was badly handled over a period of time."
A spokeswoman for the trust said: "Hywel Dda NHS Trust does not condone bullying of any kind and policies and procedures are in place to deal with any allegations of inappropriate behaviour.
"Since this case, the former Carmarthenshire NHS Trust, now part of Hywel Dda NHS Trust, reviewed systems relating to workplace health and is now identifying any additional training requirements to ensure that the issues raised in this type of case are managed appropriately for the future."
Mr Lewis declined to comment.