There is a lot of back-and-forth going on in the past, so I would suggest focusing on the present. How are you being treated by Glenn and Sam *right now?* Do they speak to you honestly and considerately? Are the conditions of living with them fair? Are the conditions of the relationship fair? Do they stick to their word? Do they honor you?
You can express thanks for someone helping you without binding yourself to a relationship that is making you unhappy. Overall, are you mostly happy in this relationship with Glenn and Sam, or is it making you mostly unhappy? Are Glenn and Sam happy with the way things are? Is their drama stressing you out?
I don't necessarily advocate leaving this relationship; it is a 50/50 call, and you have to make the call, as it is your life and welfare that's at stake. And additionally, you know better than anyone else what the situation is and what effect it's having on you. But I think GalaGirl has made excellent posts here, and I'd think about all she's said.
Make sure you take care of you, especially if Glenn and Sam are too caught up in their own drama to be of help to you. Are your wants and needs being addressed in this situation? These are things to think about.
If you decide to stay in the relationship, try to encourage all three of you to get better at communicating with each other, and at working together as a team. If things are intolerable right now, try to think of a reasonable time frame for enduring that, and tell Glenn and Sam you'll have to leave at the end of that time frame if things haven't improved.
Let the past be put in the past; forgive and forget. Focus on how things are going in the present, and on how they are likely to go in the future. Try to take a step out of your emotional self, and view the situation with logic as if you were an outsider. If you had a friend who was in your situation, and they asked you what to do, what would you tell them?
I hope things get better.
Love means never having to say, "Put down that meat cleaver!"