Congratulations
First of all you must truly be congratulated. You are very much ahead of where most people are when issues like this present themselves. You understand that every situation has a root cause. This can be stated another way. Cause...effect.
This situation likely has several contributing factors. In environmental health circles there is a concept called "total load." It is imperative to understand this metaphor. In understanding this you can easily move through your current challenge and not only reclaim your health but actually move beyond what you ever thought was possible for having amazing health. You mention that you have had a stress issue for sometime now. It would be good to explore some of the details of this. Emotions are a huge contributing factor to all dis ease. Some say it is THE most important of all contributing factors.
If no one has pointed this out to you yet, I will. There are several excellent methods for dissolving emotional blocks. The most popular method is EFT and another lesser known method is called TAT. Please look into these methods. The knowledge of these methods is freely shared and they are powerful when applied to emotions that can trigger illness.
http://www.tatlife.com/
http://www.eftuniverse.com/
Now back tho the Total Load concept. Our immune systems can be likened to a barrel. When that barrel is overflowing then we feel symptoms. Our immune systems can become impaired or challenged due to all kinds of stressors. Emotional, mental and physical stresses all impact our immune system and how it effectively deals with toxins (some of which are, ironically, stress chemicals).
So then we must look at all the negative contributing factors that can impede our immune system. Our environment and diet are two main areas that we can do much about armed with some knowledge.
You mentioned mold as a possibility. Mainstream medicine is not always much help in the area of environmental toxins such as mold or chemicals. It will be up to you to become your won detective. Perhaps reading from some environmental illness sites can help you to look for possible triggers for you asthma.
Lets take this further. ALL illness is a combination of two things which is actually one thing seen from a greater perspective. That one thing is balance. There are 2 sides of balance. In the case of health these 2 sides are toxins and nutrients. This also pertains to emotional health as well . There are toxic or beneficial emotions.
One must take stock on their life and see what is beneficial and what is harmful, environmentally, emotionally, mentally and spiritually.
For the time being it may be very helpful to try a raw, living foods diet (organic). I would also try some powerful super foods such as barley gold (excellent stuff).
For potential
parasites the easiest and most powerful way is to use diatomaceaous earth. For more systemic problems ozonated water and
Colloidal Silver can be very effective.
Keep in mind that the body is a holistic mechanism. Treating symptoms only misses the point. The major problem with mainstream medicine is that it is geared to treating symptoms and doing so with toxic chemicals.
See if your problem clears in another environment and also take steps to reduce your total toxic load. Learn about raw living foods and why it is a major step in reclaiming and maintaining optimal health.
You will reclaim your health. Then you will teach others to do the same. ;-)