...to be really hurt by this?

Son about to celebrate milestone birthday. He, and his younger brother live in the same town, about 400 miles from me. Both have kids. I try to get down there 2-4 times a year, depending on finances (I'm a pensioner). Mass invitation to the birthday issued to all friends and family - I accepted immediately, and asked, by messenger, if I could come to stay. Just received reply that birthday boy's wife's sister and family are staying in their spare room, and that I can stay with younger son. This couple and child live 100 miles away, but able to make frequent trips up. All fine, except that son 2 has recently separated and is living in a cold, unfurnished place with the only spare bed a mattress on the floor. Son 2 of course said I can have his bed. Where I'm a bit miffed is that son 1's in-laws live in the same town. and have plenty of room. As mother of the birthday boy, who has to make a long trip down, I'm really hurt that I wasn't offered the spare room. Am I being unreasonable to feel sad about this?