I've finally gotten to the point of feeling like I don't owe anyone an explanation of why I'm limping unless I feel like sharing. If I don't want to talk about it I just smile and say "yeah, how 'bout that!". Usually that works. Also, I've gotten much more cautious about what I say to others who limp or have an obvious disability...especially if I don't know
what that disability is.
As far as the memory thing goes I've found that my memory is better some days than it is on others. My cognitive abilities have definitely been affected by my MS and I probably notice it more than anyone else. My word recall is terrible. I get really frustrated at times.
I was talking to my son on the phone the other day and I said "did you ever hear from" and the cat jumped up on the table that very moment and knocked over my coffee. My whole train of thought was derailed and I didn't get to finish my question to him. Poof! The whole thought was gone.

When he asked me what I was going to ask him I told him I'd forgotten and would have to think of it later. He kept naming things that he thought might have been the subject.....I finally told him that the more he tried to make me remember the longer it would be before I actually did!
I did finally remember what it was I was going to ask him but that's how easily I can be sidetracked and gotten off course. I do it multiple times throughout the day. I have kitchen timers in various spots in the house so I don't forget things like having the iron on, or leaving a pot cooking on the stove. If I have to call someone or be anywhere at a certain time I have to set the timer to remind me. Otherwise I'll get distracted and completely forget what it was I was supposed to do.