You don't have to be a prisoner to self-sabotage. And YES, you CAN have that career you dream about! How do you stop the vicious cycle of self-sabotage? Practice!
Keep a record of how you handle stressful situations: Each time you are stressed, write down the source of the stress, what behaviors you engage in, and their consequences, good or bad. You may need to keep such a record over many days, as patterns can be difficult to identify.
From there try to determine whether your behaviors match the reasons people tend to self-sabotage-holding mistaken beliefs about the behavior or because a behavior feels right.
Then train yourself to act in a new way. Don't just stop the self-sabotage behavior; replace it with something new and healthy-something that doesn't add more problems to an already difficult situation.
Dr. Selby recommends activities that distract people from thinking about their problems-getting physically active, developing a new hobby, engaging in conversation with others (about things other than personal problems).
The final step is ensuring consistency. Trying a recommended fix (getting social or active when sad, doing something distracting when angry) once or twice doesn't work. Well, going to the gym a couple of times doesn't make you fit, either. Self-sabotage is a learned pattern; you have to take corrective action again and again if you want the changes to stick.
Practice makes perfect, so expect to repeat your efforts for a while. The average habit takes 90 days to break, so give yourself at least 3 months to practice and try again if it doesn't immediately fix your desire to procrastinate.
I recently had an actor say, "Ya know, I took all the time I had from the moment you gave me my sides until I walked into the casting itself to really figure out who my character was. It was the first time I really focused on the homework side of acting and I booked it!" Putting your best effort forth won't always result in getting the gig, but it's the only sure way to always instill confidence in the people working around you and open doors to the future. Procrastination can be detrimental to building those same relationships.
What habit are you going to work on creating for the next 90 days?