Yes, my 3 biggest reservations is
1. a bit more crowded space
2. my kids (particularly my son) dealing with sharing a room and
3. less independence.
1. Dont feel like I am wasting money on a home i spend less time in than hers.
2. Spend more time with my gf and family.
3. Less expenses
I feel like an indecisive fool and coward if i back out now, yet i know it can be much worse if i go through with it and possibly later become miserable and then back out. If i change my mind, I'm not sure how and what to say without her becoming extremely upset and feeling rejected.
But what if this is all in my head and I'm acting irrational in doubting such a move?
If you are having reservations, don't move in!!
All your reservations are valid.
The benefits seem more monetary than anything else. Saving $ is not a good reason to join households. Your children don't care about the $, all they know is that Dad is h*rney and because of that they don't get their own room anymore. If the two of you were wanting to get married, and commit for life, then it would make sense, and your children would understand it better.
You will really feel like a fool and a coward if you move in with her, it doesn't go well, and then you have to figure out how to afford to move back out.
She should not feel rejected if you do not move in. Hopefully she respects your boundaries, and your children's and your need for independence, since the two of you aren't ready to get married and share everything.
If you stopped seeing her all together, then she would have a good reason to feel rejected.