my husband took 8 months to join the church...he, like you, didn't like being pressured. you just have to be firm and ask them politely to back off...let them know you are still highly interested, but that you are needing time to search your soul, the scriptures and your prayers for answers and that you will let them know when you are ready for each next step...
are there any members you are comfortable with? that you feel you could confide in? you may let them know, or even the bishop know, that this is making you edgy and you would hate for their eagerness (which that's all it is, missionaries get so excited when someone shows interest, sometimes they can't help themselves) to push you away...
best of luck!