An old woman dying slowly and very painfully from inoperable, terminal cancer - that chooses to end her suffering, after a lifetime of goodness and happiness... I would think, has nothing to worry about.
I don't believe suicide is a one-way ticket to Hell. However, upon arrival to the afterlife, you will be shown what you missed out on, what could have been - and that may haunt you, and make you somewhat miserable for a while. -Realizing you caved in to weakness, and failure, instead of being strong and gloryfing the Lord as you should have.
But, I do believe the Lord is merciful, and sometimes misery can be downright hard, perhaps even intolerable, to cope with.
I also believe that the power to get out of here, is one power everyone should have, at all times in their life. Basically, life here sucks. You have to at least give it your all, and stick with it as long as you can - see what's around the next bend. But, after a long time, if you're overcome by a great desire to get the heck off this... 'place', then quite frankly I'm sure God can... 'relate'.
It all depends on the circumstanaces, the individual, etc. Everyone is their own unique case, that can only be judged by themselves, and God.
But again, we're here for a reason - and God above all else is power and strength, not to mention endurance & patience. So, to glorify him, you should strive to emulate those traits as best you can, as long as you can (to the very end, ideally).
There's probably a special reward for those that never stop fighting, never stop believing, never get brought down by this life. That's what I'm striving for. Why? Because damn this place - I'm not going to lose. I'm going to beat this place at it's own game. -Because if you're actually superior -as you may like to believe- then in practice, you triumph.
Winning is not so hard. Just don't dwell on the negative. Plus, look on the bright side... life is short. You'll be out of here, before too long.