Getting nauseous upon speaking or looking at my girlfriend

This might seem odd, and I really don't know where to start, I am a 20 year old male, who wants to gain weight. I have had a big problem though. I am in a long distance relationship with a wonderful girl whom i love dearly. I used to be a semi professional Tri-athlete, but i cannot compete anymore due to weightloss. The problem is that sometimes when i speak with my girlfriend or just look through her facebook profile, I start to feel nauseous and i get a gag-reflex and i eventually end up vomiting all the food i have eaten. I normally ate 5-6 times a day, this is down to 2 times a day because i simply do not have any apetite anymore. This has been going on for quite a while, back in august I was in the ER for throwing up blood, they did alot of tests, blood samples and what not, but they could not find anything. I have lost about 12 kilos in muscles during the past half year.

What is going on!? Is there anyway i can stop this? I have never had any eating disorders or illnesses before, I have actually never been to the doctor before the throwing up blood thing started... Any help or suggestions is appreciated.

Ps. Sorry for any bad grammar, I am German.

[BeeFree]

Can you recall the first time this happened? What were you doing?
If the doctors could not find anything wrong then my first guess is nerves. The body reacts in weird ways under stress, excitement or nervousness, from skin eruptions to acid and adrenaline production and so on. Some get nauseous by just the mere thought of a particular situation, others have to run to the toilet! My guess is that you work yourself up by worrying about this, and fearing it could be something more serious, which is turn makes the symptoms worse.
Try relax your mind and practise deep breathing throughout the day. Don't think too much! And pay attention to your diet. You obviously know what foods are nourishing and which to avoid, so stick with a diet that makes you feel strong and focused. When you start getting your energy back you'll know you're on the right track.

[BeeFree]

Typo:
*which IN turn makes the symptoms worse.

[anon123123]

Thanks for the response.

The first time I remember this occurred was back in June, when I thought she was cheating on me, I started to loose all appetite and got naeuseous everytime i attempted to eat anything, and if i ate to much i would simply just throw it up. Its still like this. I have never had such problems before or anything even close to this. Its starting to become really frustrating I cannot intake the amount of food i am supposed to. I am also underweight now I am 1.80 meters tall. I had a weight of 85 kilos in May now i am a mere 61 kilos. I do not know what to do. My metabolism is extremly high aswel so I HAVE to eat alot of food to gain weight, but I simply cannot, is there anyway to make yourself more hungry?