I must say the thought crossed my mind too....probably because I have seen it in real life.....
I have documented this before on this board, but in a nutshell, my father was homosexual in the 50's and 60's...and a had a partner whom it left my mother for....they were together for over 14years, and split, when his partner, decided to have a "normal" life and marry and have a family.
My Dad left him with the home that they had shared, and went off alone moving from one town to the next......Eventually he settled in a small village, and lived in a caravan park (trailer park)....ALONE.....
He visited me and my family several times, I visited him, several times, but I could always see how lonely he was.......he often used to say, that he didnt have anything to live for anymore, which used to make me angry, because he did have me, his daughter, and I had given him two grandsons....but I know now, we werent enough to give him what he longed for.
He eventually committed suicide.....
When he took his life, I was not only very sad, but I was still angry with him, because I did feel that me and my children should have been enough to make him want to continue to live on....it made me feel that he didnt love me enough to keep living for me, he didnt even want to live to watch my sons grow up...I was devastated...
When I saw the movie the first time, I thought so much of him...even though, over all the years I had seen him with his partner, and accepted that there was "something" there, it wasnt until I saw it on the screen, the depth of the love between two men, the torment they had to endure because they loved one another, and the fierce overwhelming loss of when it was all over....I finally realized that no one, not me, not my boys, no one, could have ever replaced the loss that Dad was feeling, so I didnt feel angry anymore, and I finally forgave him for taking his life away from us......and if you can understand, that I had been carrying that around with me since his death, 22 years ago, you can imagine the relief that I felt.
So, if you ask me, "would Ennis commit suicide"....I can only answer "yes".....but I really do hope that he didnt.....for as much as I have forgiven, I can still not condone it, nor agree with it.....Life deals us all some terrible and painful paths to travel, and we have to get thru them, and heal from them.....as Ennis said "If you cant fix it, you gotta stand it".......