I purchased a new LA with computer earlier this year. I do not intend to quilt as a profession, this is solely for me to enjoy. I don't use it every day, sometimes not even every week, but I wanted to be able to make my quilts from beginning to end and I did not enjoy quilting on my DSM. I tried renting time on a LA, which was nice, but the owner oversaw my work so much that I still didn't really feel like I was doing it myself, plus I didn't have the luxury of being in my own home where I could stop and do a household task in the middle of the process if I wanted to.
I spent a lot of money and my LA takes up a lot of room, but my kids are grown so we have a lot of empty space in the house and DH has a gigantic shop in which he can fiddle with tools to his heart's content. We had the money and got a good discount for paying cash.
I'm not great with the LA. There's another lady on the QB who got a LA around the same time and when I happened upon a picture of one of her quilts I felt bad at first because she's much more talented than I am, but then I reminded myself that I'm not in competition with anyone. I'm having fun doing what I enjoy.
Since you can afford it and DH is supportive, I think if you want one you should get one. Guilt can be a good emotion in the right place and time, but it doesn't sound like this is the right place or the right time for it.