I am a 73 year old single female. If I remarry, will I lose my social security?

Hi. The answer to your question depends of what type of benefits you currently receive. If you're receiving either Social Security retirement benefits based on your own earnings history or survivor benefits on the account of a deceased former spouse, then getting remarried won't affect your benefits. If you receive divorced spousal benefits on the account of a living ex-spouse, though, then a remarriage would likely cause those benefits to be terminated (https://secure.ssa.gov/apps10/poms.nsf/lnx/0300202045).

Best, Jerry