It is wonderful you are concerned about your mom, and looking for help. It sounds like your dad died very young, and that makes things particularly hard on everyone, especially
your mom. I would be happy to give you some thoughts about the treatment of her depression, but I am afraid I don't know enough about the Burgettstown area to give you the name of a specific provider or clinic. I would encourage you to call friends or family in the area for ideas. You could also call the local chapter of the Alliance for the Mentally Ill or the Pennsylvania Psychiatric Society to get referral recommendations.
The first step in evaluating someone like your mom who is depressed and has little energy, is to be sure there is not a medical illness or medication that is causing or contributing to the problem. I hope I don't offend you when I also suggest to be sure she is not abusing a drug, prescribed or not, or alcohol. Sometimes they can serve as an escape when someone is struggling with stressful life events. If you are not confident she has had a thorough medical evaluation, you might want to help her get a medical second opinion from an internal medicine doctor. Even though your mother is only 60, you might consider finding her a geriatrician for such an opinion. Again, I would suggest asking friends or relatives for a recommendation, or you could consult with the Pennsylvania Geriatric Society.
You are on the right track with the idea of physical therapy. Assuming her physician advises her it is safe, regular exercise has been shown to be very helpful in the treatment of depression. This can be any exercise she enjoys that gets her active. It sounds like she will need encouragement to get this started, but perhaps if you join her in the beginning, it will give her a boost. I would suggest she exercise at least three times a week for 30 minutes. Given the severity and chronic nature of her depression, it is also important that she meet with a mental health professional to talk about the difficulties she is experiencing. Such a professional could help her change her perspective and hopefully encourage her to be more active. I would suggest looking for someone who is skilled in cognitive-behavior therapy of depression, which has been shown to be very effective. Finally, it sounds like you will need a skilled psychiatrist to look over the medication options with her, and guide her towards something that can improve her mood and get her more active. It may be the psychiatrist will also want to do the talk therapy, or you may need a second person for that. It is hard to give you specific recommendations about medication for her without knowing more, but there are several antidepressants that tend to activate people, rather than sedate them. These include such medications as buproprion, fluoxetine, and can also include venlafaxine and duloxetine. These might be medications to discuss with her psychiatrist. It is sometimes helpful to add a stimulant to an antidepressant, and that may also be something for the psychiatrist to consider.