alc, sounds like you need to make some changes.
I know how you feel as I'm in a similar situation myself.
I'm the youngest in a large family, my siblings each having settled down and starting their own families. It finally hit home when my twin brother's wife gave birth last year that I'm approaching 30, am now single again and am not doing the thing I wanted to do when I was a child. IT really got me down and I felt really cr*p about it.
However, in true northern style, my family and friends told me to stop being such a wimp and to do something about it.
Next Tuesday I go for my medical examination and final interview to join the Royal Air Force, something I wanted to do as long as I could remember and had been kicking myself about that I hadn't done earlier.
If you are unhappy with your life, you have to make the change. Plenty of people on here and around you will give you advice and a direction to head. Its up to you and only you to take that direction. You also have age on your side, you've got your whole life ahead of you. Go get what you want.
What is it your bf wants to do? Maybe you could set each other targets to achieve together. Sit down and tell each other what you want out of life.
Hope this helps, Good luck.
K x