Why I hate training alone and why I train alone....

Except for Saturday mornings when I swim with the group, I usually do all my training alone. When I was training for IMF, I would sometimes ride with the group after swimming but often get dropped pretty much right away after we warmed up or the pace would be something I could handle but my HR would spike and coach said not to do that. Im sure I could have had a faster bike split in Florida if had kept up with the rest of the group but then again, I might have suffered some overtraining injuries as a result. Who knows, I just know I pay my coach for a reason so I should follow his program.
So, I went on my long ride with a couple of friends. We did fine for the first hour but after that, I began to lose the wheel of the person in front of me and I was struggling to keep up. My HR was going way too high for what I was trying to accomplish, 4 hour endurance ride, so I backed off. We were doing an out n back so I slowed down to reduce my HR and watched as they rode off. I didnt have my computer so I couldnt see how fast I was going but when I got dropped, our pace was up around 25mph (tailwind), unfortunately, I cant keep that up for very long. They stopped to wait for me, which brings me to the point of why I train alone. I appreciated the fact that they waited for me, but I dont like to make people wait, particularly when they are training for something as well. I like out/back's because then people dont have to wait for me. We regrouped and talked about keeping the pace down to around 20mph but I think we went over that but into a headwind, who knows. I couldnt really get a draft from either one of them so about 10 minutes into it, I suggested they go on without me and I would catch them on the other out/back section. I felt bad that I couldnt keep up, probably more frustrated than anything. Then again, I probably couldnt have kept up with them with two good legs either, both are very fit and very strong.
The day before, I had a 40 minute run to do and decided to do it with Stacey and the kids (on their bikes). We left the car, she had Koda in tow, and they ran past me. We were supposed to do a family activity but I ended up run/walking for 20 minutes by myself before I found them at the park. I was mad that they didnt wait for me but after I finished being mad, I realized that I should just do my own thing, even though it is hard to train alone, its easier on me mentally. I hate getting dropped, its very lonely.
Having said all that, I appreciate my friends and team mates waiting for me and not leaving me behind, even when we have an out n back section so dont get me wrong and read this thinking I dont enjoy riding with you, cuz I REALLY do.