Maybe you should take your joke seriously.
Telling her you'll reserve a place in your heart will
- Give her a security blanket, you've let her know that no matter
how much time it takes for you to wait. She can always come
back.
- You're always a buddy that she could trust and lean onto whenever
she faces problems, in her own r/s or any other.
- Probably, if she knows how to play 'it' well. she'll hit the soft
core of your heart periodically to maintian your liking for her.
eg. Calls/meets you to have heartfelt conversation
Conclusion: Her advantage.....
'she sorta agreed...what the hack does that mean.' - Her advantage,
since you first offer your doors wide open even she didn't
ask.
__________________________
Put her and yourself in KIV and after 4 years review this
relationship if it's possible to work out.
It is wiser for you to maintain a outward search for other
potientals then to wait and be pessimistic. If you really choose to
be a 'good' man. You'll be at your own loss.
You may be facing a opponent and hence the insecurity.
I suggest that you should find your own activity and NOT be
bothered but her and your 'rival'.
Let her know you have your busy schedule and also a good social
life. Nothing beats being a guy with many options. That way, she
knows she has competitors too. Will discuss this further next
time.
But right now, you should let her be and seek for your own
opportunities.
Being Passive is not the way to attraction - She might end up seein
you as a soul-mate then potiental.
Gain more from talking to girls/ladies and listen to them. Bother
to ask them sensitive questions about what they really want. Maybe
your next relationship will not be far. 
Meanwhile, take care.
Cheers
