Am I allowed to go to an aa meeting with a significant other if I'm not an alcoholic?

Yes. Your can definitly go for support, what you need to make sure is that the meeting you go to is an "open" meeting and not a closed meeting which is for alcoholics only.
Depends. There are two general kinds of meetings. At "open" meetings, anyone is welcome, and you can join your so. At "closed" meetings it is only for the alcoholic. However, many meetings have simultaneous alanon meetings, which are specifically for loved ones and friends, and you may get far more out of these meetings than you would at the aa meeting itself, although those meetings may also be helpful.
It would provide. You with knowledge and insight if you attend an open aa meeting. Attending aa is a great way to show support for your loved on. On the other hand, it is also important that you take good care of yourself. Living with an alcoholic can be very difficult. Ala non will provide you with support and teach you how to cope and deal with an alcoholic loved one.