My husband and I have both boated class 3-5 for many years, and have fought over where to go boat, how to run something, who to go with, time frames, etc. We have our greatest times when we are playboating together on a run we both are comfortable on (like on the Ocoee or Gauley), or we go to a hard but not too scary creek (like the Green, OBJ) and I get one good run in, he does another lap with his buddies, (or laps) and I take pictures. Those are our best days. I love those times, and so does he. But when we start trying to get me involved in going with his group somewhere that is going to challenge me, and maybe both of us, (especially mentally) then we sometimes have a problem. Its not easy to do super hard runs with your significant other. I remember a pretty tough overnighter we did alone, and had a major meltdown. Also we did a 12 mile wilderness run that was Upper Youghish difficulty (neither of us had ever done it), and didn't get done till almost midnight. We were still fighting while we ate stale, gas station burritos. He blamed me for scouting obsessively and taking too long, I blamed him for not getting on early enough and yelling at me to hurry up. But these times have been fewer than the many wonderful days we have shared. Sometimes, I have to just suck it up and set him free to boat with the guys and I go find some girls to run Tellico with.

Boater guys are quick to say that their relationship problems are due to not being allowed to boat enough. The issues you guys are having in your flailing relationships, because of boating, have just as much to do with YOUR selfishness and they do the woman's neediness. Women need to feel loved, and if you are always anxious to leave it makes us feel bad and unloved. Guys need their time to boat with their buddies, even if the significant other is a boater. And that is the issue...so solving this problem is purely a balancing act. Both parties must realize the other's needs, and accommodate. Pretty simple. 

If your girlfriend wants to learn to kayak, then great. But she has to want it for herself and learn as much from other sources like a club, as she learns from you. It would be great if you helped her get started, so you could share this together, but you need to make it very clear that even if you are both into it, you will still be boating separately sometimes. Because you NEED that. The same way she needs to spend time with you. You must understand this if you want to have a healthy relationship.