If the operator sent you the participation offer (AFE) and you didn't elect to participate, you can't lease to anyone but the operator in the spacing you received the time elapsed AFE's for.
The operators force pool the spacings as a matter of course these days even when they think they have all the interests accounted for.
Once the operator has force pooled the spacing you can't lease to anyone but the operator, BUT you can still enter into a farmout agreement with someone for future wells. You put up the minerals and your partner in the farmout agreement puts up money for drilling and expertise if you have chosen the correct partner. You still have that option.
I don't know exactly where your minerals are but I believe you are (reasonably) near the river from what you have said elsewhere and that area is generally the low/thick/rich area and your operator wouldn't like it if you participated or entered into a farmout deal with someone. The Operator might dislike the possibility enough to come to the table and negotiate a lease in earnest, should you still wish to lease.
It's a good time to be looking for a partner. Drilling cost is down to 2/3 the cost of what it was previously. My most recent wells are scheduled to have 50% more frack stages for 2/3 the cost of my 2011 wells. Things are definitely looking up.