Given the circumstances, that you have no mikveh within walking distance and that you are trying to conceive, there is room to permit immersion late Friday afternoon, allowing yourself enough time to make it home for candle lighting. Your husband should be out of the house when you return, and you may not see each other until after nightfall. You should discuss this with the mikveh attendant in advance to arrange the logistics.
Please feel free to get back to us with any further questions.
B’Hatzlacha!