Would appreciate some advice on Gross misconduct please

[coco1234]

In may 2014 my part time position as events manager at a College was put at risk of redundancy. I was later told this would happen and there would be a number of redundancies in the college due to budgetary constraints, so far I think my position is the only one to be made redundant. I was the only person in a team of 5 to be put forward for redundancy, there was no pool, due to work loads and my skills/capability my manager tried to block the redundancy but was told it would happen and my role would need to be taken on by the rest of the team. I had felt the decision was very personal as the director had pointed out previously that I was too feisty. I found situation very stressful. Other members of my team had also felt that I had been treated unfairly. As a result my manager and 2 other members of our team have since resigned and found other jobs. Once I was put at risk of redundancy I was lucky enough to find another job as events manager for another company. These rles were now both part time and I was planning on doing both jobs, which both employers agreed was ok as there was no conflict of interest. The college became more stressful and the doctor signed me off sick due to anxiety and stress. I did continue with the new job as this is not causing me any stress. On Friday I received a letter from the college saying that I had committed gross misconduct and they were terminating my contract with immediate effect as I was working whilst of sick with them. I have since found on the HMRC website that you are able to have 2 contracts of employment and you can be of sick from one job and not another, so I am not breaking any contracts, it is simply that I cannot bare going to a job where it causes me so much stress. I do feel very victimised and that I am being treated very unfairly. I would be very grateful if you could please give me some guidance on where I stand.